Treatise on Law
(Summa Theologica, Questions 90-97)
With an Introduction
by Stanley Parry
A GATEWAY EDITION
Chicago HENRY REGNERY COMPANY
Reprinted from the Summa Theologica
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Inc., publishers and copyright owners.
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QUESTION 90: Of the Essence of Law i
QUESTION 9 1 : Of the Various Kinds of Law 1 1
QUESTION 92: Of the Effects of Law 30
QUESTION 93: Of the Eternal Law 35
QUESTION 94: Of the Natural Law 54
QUESTION 95: Of Human Law 73
QUESTION 96: Of the Power of Human Law 87
QUESTION 97: Of Change in Laws 105
Aquinas' Philosophy of Law
IN THE Treatise on Law, Aquinas offers a philo-
sophical analysis of the structure of law. The deeper
significance of this analysis lies in its struggle with
the problem of moral obligation in the political order,
a problem which Aquinas approaches with an observa-
tion of fact and an interpretation of that fact. The
observation of fact is that men in society live under
law; the interpretation of the fact is that law
achieves its results by imposing moral obligation
rather than outright force on those subject to it.
Out of such an interpretation the problem arises:
what is the source of this obligation? Aquinas does
not ask why men live under law, nor is he formally
concerned with proving that law imposes moral ob-
ligation. His concern focuses almost exclusively on
one problem, that of the roots of obligation. The
problem is basic because it asks, in effect, by what
warrant the human legislator binds the consciences
of men. Is not this a power that belongs to God alone?
If men possess it, what are the limits within which
they may exercise it?
The answer Aquinas gives to these questions is a
simple one: "Laws framed by men are either just or
unjust. If they be just, they have the power of bind-
ing in conscience, from the eternal law whence they
are derived. . . ." (Quest. 96, art. 4). The thought
leading to this conclusion, though complex in its full
expression, advances through three simple and basic
propositions: (i) obligation is a property that inheres
in the nature of things (Quest. 95, art. 2), (2) since
man has no control over the nature of things, he has
no power to determine the basic outlines of obliga-
tion (Quest. 93, art. 5), and (3) since the nature
of finite things is not self-explanatory, the ultimate
source of obligation must be found in the infinite
Being who does determine the nature of things
(Quest. 93, art. 4). Thus the source of obligation is
in the divine conception of the order proper to the
universe. As Aquinas concludes: ". . . the plan of
government is derived by secondary governors from
the governor in chief. . . . Since then the eternal law
is the plan of government in the Chief Governor, all
the plans of government in the inferior governors
must be derived from the eternal law" (Quest. 93,
Even this brief outline of his answer distinguishes
Aquinas from those whose theories are based on the
Hobbesian hypothesis that human will,, whether indir ,
vidual or corporate, can originate law. The great
truth stressed is that law, insofar as it is morally
obligating, must be rooted in God. Although there
is a human authority residing in the people by force
of nature (Quest. 90, art. 3), not even the people
are the original possessors of this power to impose
obligation. Aquinas rejects the Divine Right theory
because it explains the power of law to bind con-
science by attributing a divine quality to political
authority. No political authority, not even the sover-
eign authority, can impose an obligation on the
citizen where it is not already latent in the nature of
Granted that human law must conform to eternal
law, the human legislator still must have some way
of discovering what the directives of eternal law are.
The Romanticist solves the problem by his direct ac-
ceptance of primitive nature. But this acceptance
rests on an emotional or instinctive basis which
Aquinas cannot admit. His own solution is an intel-
lectualist one which begins with the premise: "Now
the rule and measure of human acts is the reason,
which is the first principal of human acts. . . . Con-
sequently it follows that law is something pertaining
to reason" (Quest. 90, art. i). Therefore, just as
human law does not impose obligation until it is
known to the subject, so also eternal law cannot
guide the human legislator until its directives are
made evident to him in some way. The use of the
terms "right reason" and "natural law," which is
sometimes confusing to the reader, becomes clear
when one keeps in mind that man must know the
law of nature before it can become a guide to action.
Obligation lies in the nature of things, but it orig-
inates in the mind of God and terminates in the
mind of man. Natural law is the objective link be-
tween the mind of man and the mind of God. Right
eternal law through its understanding of the moral
reason is human reason acting in harmony with
imperatives inherent in the nature of things.
By creation God sets finite beings in existence apart
from Himself. Each of these beings has a nature. Na-
tures or natural things, as Aristotle defines them, are
those things which "have within [themselves] a
principle of motion and of stationariness." Now for
our purposes, the most relevant aspect of this princi-
ple has to do with growth. In the case of man, growth
is achieved most obviously in the physical order. But
man "grows" in other ways: his intellect develops, his
will stabilizes on morally good objects. Such growth,
however, is not automatic as in the physical order,
but the result of a consciously organized plan of
action. The general outlines of this plan of action are
pre-determined by the tendencies of man's nature,
just as the growth of man's body is pre-determined by
tendencies inherent in the physical parts of his nature.
Man must therefore read nature in order to discover
the type of action by which human nature -is per-
fected. Since eternal law is promulgated in the
natural order by the very creation of natures, it
follows that natural law is not something different
from eternal law but rather a "participation thereof"
(Quest. 91, art. 2) which the human legislator must
study to discover the mind of God (Quest. 92, art.
2 and 3 ) .
This idea of the way eternal law is promulgated is
fundamental to Aquinas 's theory of how obligation is
transmitted from God to human legislator to citizen.
It keeps before our minds that the issue is not the
transfer of a right to rule but the source of the
authority which a rightful ruler exercises.
Thus, Aquinas' explanation of the origins of obli-
gation depends on his conception of natural law. It
is through the mind's ability to recognize the impera-
tives of nature that God communicates to man the
basic patterns of action proper to him. Moreover, in
this process man does not play the part of an autom-
aton. He does not dangle at the end of cosmic pup-
pet strings. Both eternal and natural law are gen-
eralized patterns of action, and man, therefore, in
determining action in the concrete circumstances of
life, contributes something to the determination of
right action. The three laws eternal, natural and
human are not three independent rules of action
but one rule progressively specified (Quest. 95, art.
With regard to such political problems as the form
of government and the wisdom of particular public
policies, the Treatise has nothing to say. Basic to it,
however, is an implied position on the relationship be-
tween law and freedom which, if accepted, will pro-
foundly influence one's conception of the problem of
politics. In the Thomistic philosophy of law, human
liberty is not an absolute condition. Man exists in the
midst of realities which he must recognize and respect
if he is to live a human life. He is inherently limited,
both morally and physically, by laws that determine the
total order of which he is a part. Freedom, or free will,
consequently, is the faculty of judging for oneself the
demands of reality. As Laversin says: "The autonomy
of the individual will can be understood only as an
abstraction, that is to say, only by considering man's
power to act as existing independently of his being
and the conditions of actual existence." Law, insofar
as it puts into concrete terms the general imperatives
of nature, is not an adventitious limiting of action.
Rather it is a conscious recognition and corporate
specification of the natural boundaries of action in
the real conditions of life. Thus law is perfectly
compatible with the freedom proper to man.
This is not to deny that problems arise with regard
to the government that makes the law. For it does
not follow from this harmony between law and free-
dom that a just law cannot also be oppressive. But it
does mean that a political philosophy based on the
premise of harmony will be radically different from
philosophies that begin with a premise of conflict.
Utilitarian thought, for instance, begins with the
premise that action under law is not free. Behind this
premise is the idea that spontaneity is the essential
element in freedom. Law, by imposing a rule of
action on the citizen in the name of the group, de-
stroys this element of spontaneity and so freedom.
From these two positions there follow two different
conceptions of the problem of politics. The problem
for the Thomist is to work out a system of govern-
ment that will realize in fact the theoretical harmony
between law and freedom. The problem for the Utili-
tarian is to work out a system that will sacrifice as
little freedom as is compatible with the preservation
of order. The one philosophy supports the theory that
all men can conceivably achieve complete freedom;
the other begins by supposing that a sacrifice of free-
dom is inevitable.
University of Notre Dame
OF THE ESSENCE OF LAW
(In Four Articles)
WE have now to consider the extrinsic principles of
acts. Now the extrinsic principle inclining to evil is
the devil, of whose temptations we have spoken in
the First Part (Q. CXIV.) . But the extrinsic principle
moving to good is God, Who both instructs us by
means of His Law, and assists us by His Grace:
wherefore in the first place we must speak of law; in
the second place, of grace.
Concerning law, we must consider ( i ) Law itself
in general; (2) Its parts. Concerning law in general
three points offer themselves for our consideration:
(i) Its essence; (2) The different kinds of law; (3)
The effects of law.
Under the first head there are four points of in-
quiry: (r) Whether law is something pertaining to
reason? (2) Concerning the end of law. (3) Its
cause. (4) The promulgation of law.
TREATISE ON LAW
WHETHER LAW IS SOMETHING PERTAINING
We proceed thus to the First Article:
Objection i. It would seem that law is not some-
thing pertaining to reason. For the Apostle says
(Rom. vii. 23): Z see another law in my members,
etc. But nothing pertaining to reason is in the mem-
bers; since the reason does not make use of a bodily
organ. Therefore law is not something pertaining to
Ob}. 2. Further, in the reason there is nothing else
but power, habit, and act. But law is not the power
itself of reason. In like manner, neither is it a habit
of reason: because the habits of reason are the intel-
lectual virtues of which we have spoken above (Q.
LVII. ) . Nor again is it an act of reason : because then
law would cease, when the act of reason ceases, for in-
stance, while we are asleep. Therefore law is nothing
pertaining to reason.
Obj. 3. Further, the law moves those who are sub-
ject to it to act aright. But it belongs properly to the
will to move to act, as is evident from what has been
said above (Q. IX., A. i). Therefore law pertains,
not to the reason, but to the will; according to the
words of the Jurist (Lib. i. ff., De Const. Prin. leg.
i.) : Whatsoever please th the sovereign, has force of
OF THE ESSENCE OF LAW 3
On the contrary, It belongs to the law to command
and to forbid. But it belongs to reason to command,
as stated above (Q. XVII., A. i). Therefore law is
something pertaining to reason.
I answer that, Law is a rule and measure of acts,
whereby man is induced to act or is restrained from
acting: for lex (law) is derived from ligare (to
bind), because it binds one to act. Now the rule and
measure of human acts is the reason, which is the
first principle of human acts, as is evident from what
has been stated above (Q. I., A. i ad 3); since it
belongs to the reason to direct to the end, which is
the first principle in all matters of action, according
to the Philosopher (Pbys. ii.). Now that which is the
principle in any genus, is the rule and measure of that
genus: for instance, unity in the genus of numbers,
and the first movement in the genus of movements.
Consequently it follows that law is something per-
taining to reason.
Reply Obj. i. Since law is a kind of rule and meas-
ure, it may be in something in two ways. First, as
in that which measures and rules: and since this is
proper to reason, it follows that, in this way, law is
in the reason alone. Secondly, as in that which is
measured and ruled. In this way, law is in all those
things that are inclined to something by reason of
some law: so that any inclination arising from a law,
may be called a law, not essentially but by participa-
tion as it were. And thus the inclination of the mem-
bers to concupiscence is called the law of the
Reply Obj. 2. Just as, in external action, we may
4 TREATISE ON LAW
consider the work and the work done, for instance
the work of building and the house built; so in the
acts of reason, we may consider the act itself of rea-
son, i.e., to understand and to reason, and something
produced by this act. With regard to the speculative
reason, this is first of all the definition; secondly, the
proposition; thirdly, the syllogism or argument. And
since also the practical reason makes use of a syllo-
gism in respect of the work to be done, as stated above
(Q. XIII., A. 3; Q. LXXVL, A. i) and as the Phi-
losopher teaches (Ethic, vii. 3); hence we find in
the practical reason something that holds the same
position in regard to operations, as, in the speculative
intellect, the proposition holds in regard to conclu-
sions. Suchlike universal propositions of the practical
intellect that are directed to actions have the nature
of law. And these propositions are sometimes under
our actual consideration, while sometimes they are
retained in the reason by means of a habit.
Reply Ob}. 3. Reason has its power of moving
from the will, as stated above (Q. XVIL, A. i) : for
it is due to the fact that one wills the end, that the
reason issues its commands as regards things ordained
to the end. But in order that the volition of what is
commanded may have the nature of law, it needs to
be in accord with some rule of reason. And in this
sense is to be understood the saying that the will of
the sovereign has the force of law; otherwise the
sovereign's will would savour of lawlessness rather
than of law.
OF THE ESSENCE OF LAW-
WHETHER THE LAW IS ALWAYS DIRECTED TO THE
We proceed thus to the Second Article:
Objection i. It would seem that the law is not
always directed to the common good as to its end.
For it belongs to law to command and to forbid. But
commands are directed to certain individual goods.
Therefore the end of the law is not always the com-
Obj. 2. Further, the law directs man in his actions.
But human actions are concerned with particular
matters. Therefore the law is directed to some partic-
Obj. 3. Further, Isidore says (Etym. v. 3): If the
law is based on reason, whatever is based on reason
will be a law. But reason is the foundation not only
of what is ordained to the common good, but also of
that which is directed to private good. Therefore the
law is not only directed to the good of all, but also to
the private good of an individual.
On the contrary) Isidore says (Etym. v. 21) that
laws are enacted for no private profit, but for the
common benefit of the citizens.
I answer that, As stated above (A. i ) , the law be-
longs to that which is a principle of human acts,
because it is their rule and measure. Now as reason
6 TREATISE ON LAW
is a principle of human acts, so in reason itself there
is something which is the principle in respect of all
the rest: wherefore to this principle chiefly and
mainly law must needs be referred. Now the first
principle in practical matters, which are the object of
the practical reason, is the last end: and the last end
of human life is bliss or happiness, as stated above
(Q. II., A. 7; Q. III., A. i). Consequently the law
must needs regard principally the relationship to hap-
piness. Moreover, since every part is ordained to the
whole, as imperfect to perfect; and since one man is a
part of the perfect community, the law must needs
regard properly the relationship to universal happiness.
Wherefore the Philosopher, in the above definition of
legal matters mentions both happiness and the body
politic: for he says (Ethic, v. i) that we call those
legal matters just, which are adapted to produce and
preserve happiness and its parts for the body politic:
since the state is a perfect community, as he says in
Polit. i. i.
Now in every genus, that which belongs to it chiefly
is the principle of the others, and the others belong
to that genus in subordination to that thing: thus
fire, which is chief among hot things, is the cause of
heat in mixed bodies, and these are said to be hot in
so far as they have a share of fire. Consequently,
since the law is chiefly ordained to the common good,
any other precept in regard to some individual work,
must needs be devoid of the nature of a law, save in
so far as it regards the common good. Therefore every
law is ordained to the common good.
OF THE ESSENCE OF LAW /
Reply Obj. i. A command denotes an application
of a law to matters regulated by the law. Now the
order to the common good, at which the law aims, is
applicable to particular ends. And in this way com-
mands are given even concerning particular matters.
Reply Obj. 2. Actions are indeed concerned with
particular matters: but those particular matters are
referable to the common good, not as to a common
genus or species, but as to a common final cause, ac-
cording as the common good is said to be the com-
Reply Obj. 3. Just as nothing stands firm with
regard to the speculative reason except that which is
traced back to the first indemonstrable principles, so
nothing stands firm with regard to the practical rea-
son, unless it be directed to the last end which is the
common good: and whatever stands to reason in this
sense, has the nature of a law.
WHETHER THE REASON OF ANY MAN IS
COMPETENT TO MAKE LAWS?
We proceed thus to the Third Article:
Objection i. It would seem that the reason of any
man is competent to make laws. For the Apostle says
(Rom. ii. 14) that when the Gentiles, who have not
the law, do by nature those things that are of the
law, . . . they are a law to themselves. Now he says
8 TREATISE ON LAW
this of all in general. Therefore anyone can make a
law for himself.
Ob}. 2. Further, as the Philosopher says (Ethic, ii.
i), the intention of the lawgiver is to lead men to
virtue. But every man can lead another to virtue.
Therefore the reason of any man is competent to make
Obj. 3. Further, just as the sovereign of a state
governs the state, so every father of a family governs
his household. But the sovereign of a state can make
laws for the state. Therefore every father of a family
can make laws for his household.
On the contrary, Isidore says (Etym. v. 10): A
law is an ordinance of the people whereby something
is sanctioned by the Elders together with the Com-
I answer that, A law, properly speaking, regards
first and foremost the order to the common good.
Now to order anything to the common good, belongs
either to the whole people, or to someone who is the
vicegerent of the whole people. And therefore the
making of a law belongs either to the whole people
or to a public personage who has care of the whole
people: since in all other matters the directing of
anything to the end concerns him to whom the end
Reply Obj. i. As stated above (A. i ad i), a law
is in a person not only as in one that rules, but also
by participation as in one that is ruled. In the latter
way each one is a law to himself, in so far as he
shares the direction that he receives from one who
OF THE ESSENCE OF LAW 9
rules him. Hence the same text goes on: Who show
the work of the law written in their hearts.
Reply Ob}. 2. A private person cannot lead another
to virtue efficaciously: for he can only advise, and
if his advice be not taken, it has no coercive power,
such as the law should have, in order to prove an
efficacious inducement to virtue, as the Philosopher
says (Ethic, x. 9). But this coercive power is vested
in the whole people or in some public personage, to
whom it belongs to inflict penalties, as we shall state
further on (Q. XCIL, A. 2 ad 3; II-IL, Q. LXIV., A.
3). Wherefore the framing of laws belongs to him
Reply Obj. 3. As one man is a part of the house-
hold, so a household is a part of the state: and the
state is a perfect community, according to Polit. i.
i. And therefore, as the good of one man is not the
last end, but is ordained to the common good; so too
the good of one household is ordained to the good
of a single state, which is a perfect community.
Consequently he that governs a family, can indeed
make certain commands or ordinances, but not such
as to have properly the force of law.
WHETHER PROMULGATION IS ESSENTIAL
TO A LAW?
We proceed thus to the Fourth Article:
Objection i. It would seem that promulgation is
10 TREATISE ON LAW
not essential to a law. For the natural law above all
has the character of law. But the natural law needs
no promulgation. Therefore it is not essential to a law
that it be promulgated.
Ob]. 2. Further, it belongs properly to a law to
bind one to do or not to do something. But the
obligation of fulfilling a law touches not only those
in whose presence it is promulgated, but also others.
Therefore promulgation is not essential to a law.
Obj. 3. Further, the binding force of a law extends
even to the future, since laws are binding in matters
of the future, as the jurists say (Cod. I., tit. De lege
et cons tit. leg. vii. ) . But promulgation concerns those
who are present. Therefore it is not essential to a
On the contrary, It is laid down in the Decretals,
dist. 4, that laws are established when they are
1 answer that, As stated above (A. i), a law is
imposed on others by way of a rule and measure.
Now a rule or measure is imposed by being applied
to those who are to be ruled and measured by it.
Wherefore, in order that a law obtain the binding
force which is proper to a law, it must needs be
applied to the men who have to be ruled by it. Such
application is made by its being notified to them by
promulgation. Wherefore promulgation is necessary
for the law to obtain its force.
Thus from the four preceding articles, the defini-
tion of law may be gathered; and it is nothing else
than an ordinance of reason for the common good,
OF THE VARIOUS KINDS OF LAW n
made by him who has care of the community, and
Reply Obj. i. The natural law is promulgated by
the very fact that God instilled it into man's mind
so as to be known by him naturally.
Reply Obj. 2. Those who are not present when a
law is promulgated, are bound to observe the law,
in so far as it is notified or can be notified to them
by others, after it has been promulgated.
Reply Obj. 3. The promulgation that takes place
now, extends to future time by reason of the dura-
bility of written characters, by which means it is
continually promulgated. Hence Isidore says (Etym.
v. 3; ii. 10) that lex (law) is derived from legere
(to read) because it is written.
OF THE VARIOUS KINDS OF LAW
(In Six Articles)
must now consider the various kinds of law:
under which head there are six points of inquiry : ( i )
Whether there is an eternal law? (2) Whether there
is a natural law? (3) Whether there is a human law?
(4) Whether there is a Divine law? (5) Whether
there is, one Divine law, or several? (6) Whether there
is a law of sin?
12 TREATISE ON LAW
WHETHER THERE IS AN ETERNAL LAW?
We proceed thus to the First Article:
Objection i. It would seem that there is no
eternal law. Because every law is imposed on some-
one. But there was not someone from eternity on
whom a law could be imposed: since God alone was
from eternity. Therefore no law is eternal.
Ob}. 2. Further, promulgation is essential to law.
But promulgation could not be from eternity: be-
cause there was no one to whom it could be pro-
mulgated from eternity. Therefore no law can be
Ob}. 3. Further, a law implies order to an end.
But nothing ordained to an end is eternal: for the
last end alone is eternal. Therefore no law is eternal.
On the contrary, Augustine says (De Lib. Arb.
i. 6) : That Law which is the Supreme Reason cannot
be understood to be otherwise than unchangeable and
I answer that, As stated above (Q. XC., A. i ad
2; AA. 3, 4), a law is nothing else but a dictate of
practical reason emanating from the ruler who
governs a perfect community. Now it is evident,
granted that the world is ruled by Divine Provi-
dence, as was stated in the- First Part (Q. XXIL, AA.
i, 2), that the whole community of the universe is
OF THE VARIOUS KINDS OF LAW 13
governed by Divine Reason. Wherefore the very
Idea of the government of things in God the Ruler
of the universe, has the nature of a law. And since
the Divine Reason's conception of things is not sub-
ject to time but is eternal, according to Prov. viii.
23, therefore it is that this kind of law must be called
Reply Obj. i. Those things that are not in them-
selves, exist with God, inasmuch as they are fore-
known and pre-ordained by Him, according to Rom.
iv. 17: Who calls those things that are not, as those
that are. Accordingly the eternal concept of the
Divine law bears the character of an eternal law, in
so far as it is ordained by God to the government of
things foreknown by Him.
Reply Obj. 2. Promulgation is made by word of
mouth or in writing; and in both ways the eternal
law is promulgated: because both the Divine Word
and the writing of the Book of Life are eternal. But
the promulgation cannot be from eternity on the
part of the creature that hears or reads.
Reply Obj. 3. The law implies order to the end
actively, in so far as it directs certain things to the
end; but not passively, that is to say, the law itself
is not ordained to the end, except accidentally, in a
governor whose end is extrinsic to him, and to which
end his law must needs be ordained. But the end
of the Divine government is God Himself, and His
law is not distinct from Himself. Wherefore the
eternal law is not ordained to another end.
14 TREATISE ON LAW
WHETHER THERE IS A NATURAL LAW?
We proceed thus to the Second Article:
Objection i. It would seem that there is no natural
law in us. Because man is governed sufficiently by the
eternal law: for Augustine says (De Lib. Arb. i)
that the eternal law is that by which it is right that
all things should be most orderly. But nature does
not abound in superfluities as neither does she fail
in necessaries. Therefore no law is natural to man.
Obj. 2. Further, by the law man is directed, in
his acts, to the end, as stated above (Q. XC., A. 2).
But the directing of human acts to their end is not
a function of nature, as is the case in irrational
creatures, which act for an end solely by their natural
appetite; whereas man acts for an end by his reason
and will. Therefore no law is natural to man.
Obj. 3. Further, the more a man is free, the less
is he under the law. But man is freer than all the
animals, on account of his free-will, with which he
is endowed above all other animals. Since therefore
other animals are not subject to a natural law, neither
is man subject to a natural law.
On the contrary, A gloss on Rom. ii. 14: "When
the Gentiles, who have not the law, do by nature
those things that are of the law, comments as fol-
lows: Although they have no written law, yet they
OF THE VARIOUS KINDS OF LAW 1$
have the natural law, whereby each one knows, and
is conscious of, what is good and what is evil.
I answer that, As stated above (Q. XC., A. r ad
i ) , law, being a rule and measure, can be in a person
in two ways: in one way, as in him that rules and
measures; in another way, as in that which is ruled
and measured, since a thing is ruled and measured, in
so far as it partakes of the rule or measure. Where-
fore, since all things subject to Divine providence
are ruled and measured by the eternal law, as was
stated above (A. i ) ; it is evident that all things
partake somewhat of the eternal law, in so far as,
namely, from its being imprinted on them, they
derive their respective inclinations to their proper
acts and ends. Now among all others, the rational
creature is subject to Divine providence in the most
excellent way, in so far as it partakes of a share of
providence, by being provident both for itself and
for others. "Wherefore it has a share of the Eternal
Reason, whereby it has a natural inclination to its
proper act and end: and this participation of the
eternal law in the rational creature is called the
natural law. Hence the Psalmist after saying (Ps. iv.
6) : Offer up the sacrifice of justice, as though some-
one asked what the works of justice are, adds: Many
say, Who showeth us good things? in answer to
which question he says: The light of Thy counten-
ance, O Lord, is signed upon us: thus implying that
the light of natural reason, whereby we discern what
is good and what is evil, which is the function of the
natural law, is nothing else than an imprint on us of
1 6 TREATISE ON LAW
the Divine light. It is therefore evident that the
natural hw is nothing else than the rational crea-
ture's participation of the eternal law.
Reply Ob}, i. This argument would hold, if the
natural law were something different from the eternal
law: whereas it is nothing but a participation thereof,
as stated above.
Reply Ob}. 2. Every act of reason and will in us
is based on that which is according to nature, as
stated above (Q. X., A. i): for every act of reason-
ing is based on principles that are known naturally,
and every act of appetite in respect of the means is
derived from the natural appetite in respect of the
last end. Accordingly the first direction of our acts
to their end must needs be in virtue of the natural
Reply Ob]. 3. Even irrational animals partake in
their own way of the Eternal Reason, just as the
rational creature does. But because the rational
creature partakes thereof in an intellectual and ra-
tional manner, therefore the participation of the
eternal law in the rational creature is properly called
a law, since a law is something pertaining to reason,
as stated above (Q. XC., A. i). Irrational creatures,
however, do not partake thereof in a rational man-
ner, wherefore there is no participation of the eternal
law in them, except by way of similitude.
OF THE VARIOUS KINDS OF LAW 17
WHETHER THERE IS A HUMAN LAW?
We proceed thus to the Third Article:
Objection i. It would seem that there is not a
human law. For the natural law is a participation of
the eternal law, as stated above (A. 2). Now through
the eternal law all things are most orderly, as Augus-
tine states (De Lib. Arb. i. 6). Therefore the natural
law suffices for the ordering of all human affairs.
Consequently there is no need for a human law.
Obj. 2. Further, a law bears the character of a
measure, as stated above (Q. XC., A. i). But human
reason is not a measure of things, but vice versa, as
stated in Metapb. x., text 5. Therefore no law can
emanate from human reason.
Obj. 3. Further a measure should be most certain,
as stated in Metapb. x., text. 3. But the dictates of
human reason in matters of conduct are uncertain,
according to Wis. ix. 14: The thoughts of mortal
men are fearful, and our counsels uncertain. There-
fore no law can emanate from human reason.
On the contrary, Augustine (De Lib. Arb. i. 6),
distinguishes two kinds of law, the one eternal, the
other temporal, which he calls human.
I answer that, As stated above (Q. XC., A. i ad
2), a law is a dictate of the practical reason. Now
it is to be observed that the same procedure takes
1 8 TREATISE ON LAW
place in the practical and in the speculative reason:
for each proceeds from principles to conclusions, as
stated above (ibid.). Accordingly we conclude that
just as, in the speculative reason, from naturally
known indemonstrable principles, we draw the con-
clusions of the various sciences, the knowledge of
which is not imparted to us by nature, but acquired
by the efforts of reason, so too it is from the precepts
of the natural law, as from general and indemon-
strable principles, that the human reason needs to
proceed to the more particular determination of cer-
tain matters. These particular determinations, devised
by human reason, are called human laws, provided
the other essential conditions of law be observed, as
stated above (Q. XC, AA. 2, 3, 4). Wherefore
Tully says in his Rhetoric (De Invent. Rhet. ii.)
that justice has its source in nature; thence certain
things came into custom by reason of their utility;
afterwards these things which emanated from nature
and were approved by custom, were sanctioned by
fear and reverence for the law.
Reply Ob), i. The human reason cannot have a
full participation of the dictate of the Divine Reason,
but according to its own mode, and imperfectly.
Consequently, as on the part of the speculative rea-
son, by a natural participation of Divine Wisdom,
there is in us the knowledge of certain general prin-
ciples, but not proper knowledge of each single truth,
such as that contained in the Divine Wisdom; so too,
on the part of the practical reason, man has a natural
participation of the eternal law, according to certain
OF THE VARIOUS KINDS OF LAW 19
general principles, but not as regards the particular
determinations of individual cases, which are, how-
ever, contained in the eternal law. Hence the need
for human reason to proceed further to sanction them
Reply Obj. 2. Human reason is not, of itself, the
rule of things: but the principles impressed on it by
nature, are general rules and measures of all things
relating to human conduct, whereof the natural rea-
son is the rule and measure, although it is not the
measure of things that are from nature.
Reply Obj. 3. The practical reason is concerned
with practical matters, which are singular and con-
tingent: but not with necessary things, with which
the speculative reason is concerned. Wherefore human
laws cannot have that inerrancy that belongs to the
demonstrated conclusions of sciences. Nor is it neces-
sary for every measure to be altogether unerring and
certain, but according as it is possible in its own
WHETHER THERE WAS ANY NEED FOR A
We proceed thus to the Fourth Article:
Objection i. It would seem that there was no need
for a Divine law. Because, as stated above (A. 2),
the natural law is a participation in us of the eternal
20 TREATISE ON LAW
law. But the eternal law is a Divine law, as stated
above (A. i ) . Therefore there is no need for a Divine
law in addition to the natural law, and human laws
Ob}, z. Further, it is written (Ecclus. xv. 14)
that God left man in the hand of his own counsel.
Now counsel is an act of reason, as stated above (Q.
XIV., A. i ) . Therefore man was left to the direction
of his reason. But a dictate of human reason is a
human law, as stated above (A. 3). Therefore there
is no need for man to be governed also by a Divine
Ob}. 3. Further, human nature is more self-
sufficing than irrational creatures. But irrational crea-
tures have no Divine law besides the natural in-
clination impressed on them. Much less, therefore,
should the rational creature have a Divine law in
addition to the natural law.
On the contrary, David prayed God to set His
law before him, saying (Ps. cxviii. 33): Set before
me for a law the way of Thy justifications, O Lord.
I answer that, Besides the natural and the human
law it was necessary for the directing of human con-
duct to have a Divine law. And this for four reasons.
First, because it is by law that man is directed how
to perform his proper acts in view of his last end.
And indeed if man were ordained to no other end
than that which is proportionate to his natural
faculty, there would be no need for man to have
any further direction on the part of his reason, be-
sides the natural law and human law which is
OF THE VARIOUS KINDS OF LAW 21
derived from it. But since man is ordained to an end
of eternal happiness which is inproportionate to man's
natural faculty, as stated above (Q. V., A. 5), there-
fore it was necessary that, besides the natural and
the human law, man should be directed to his end
by a law given by God.
Secondly, because, on account of the uncertainty
of human judgment, especially on contingent and
particular matters, different people form different
judgments on human acts; whence also different and
contrary laws result. In order, therefore, that man
may know without any doubt what he ought to do
and what he ought to avoid, it was necessary for man
to be directed in his proper acts by a law given by
God, for it is certain that such a law cannot err.
Thirdly, because man can make laws in those
matters of which he is competent to judge. But
man is not competent to judge of interior move-
ments, that are hidden, but only of exterior acts
which appear: and yet for the perfection of virtue
it is necessary for man to conduct himself aright in
both kinds of acts. Consequently human law could
not sufficiently curb and direct interior acts; and
it was necessary for this purpose that a Divine law
Fourthly, because, as Augustine says (De Lib. Arb.
i. 5, 6), human law cannot punish or forbid all evil
deeds: since while aiming at doing away with all
evils, it would do away with many good things, and
would hinder the advance of the common good,
which is necessary for human intercourse. In order
22 TREATISE ON LAW
therefore, that no evil might remain unforbidden
and unpunished, it was necessary for the Divine law
to supervene, whereby all sins are forbidden.
And these four causes are touched upon in Ps.
cxviii. 8, where it is said: The law of the Lord is
unspotted, i.e., allowing no foulness of sin; con-
verting souls, because it directs not only exterior, but
also interior acts; the testimony of the Lord is faith-
ful, because of the certainty of what is true and
right; giving u-'isdom to little ones, by directing man
to an end supernatural and Divine.
Reply Obj. i. By the natural law the eternal law
is participated proportionately to the capacity of
human nature. But to his supernatural end man needs
to be directed in a yet higher way. Hence the ad-
ditional law given by God, whereby man shares more
perfectly in the eternal law.
Reply Obj. 2. Counsel is a kind of inquiry: hence
it must proceed from some principles. Nor is it
enough for it to proceed from principles imparted
by nature, which are the precepts of the natural law,
for the reasons given above: but there is need for
certain additional principles, namely, the precepts of
the Divine law.
Reply Obj. 3. Irrational creatures are not ordained
to an end higher than that which is proportionate
to their natural powers: consequently the comparison
OF THE VARIOUS KINDS OF LAW-
WHETHER THERE IS BUT ONE DIVINE LAW?
We proceed thus to the Fifth Article:
Objection i. It would seem that there is but one
Divine law. Because, where there is one king in one
kingdom there is but one law. Now the whole of
mankind is compared to God as to one king, accord-
ing to Ps. xlvi. 8 : God is King of all the earth. There-
fore there is but one Divine law.
Ob}. 2. Further, every law is directed to the end
which the lawgiver intends for those for whom he
makes the law. But God intends one and the same
thing for all men; since according to i Tim. ii. 4:
He will have all men to be saved, and to come to the
knowledge of the truth. Therefore there is but one
Ob}. 3. Further, the Divine law seems to be more
akin to the eternal law, which is one, than the natural
law, according as the revelation of grace is of a higher
order than natural knowledge. Therefore much more
is the Divine law but one.
On the contrary. The Apostle says (Heb. vii. 12) :
The priesthood being translated, it is necessary that
a translation also be made of the law. But the priest-
hood is twofold, as stated in the same passage, viz.,
24 TREATISE ON LAW
the levitical priesthood, and the priesthood of Christ.
Therefore the Divine law is twofold, namely, the
Old Law and the New Law.
/ answer that, As stated in the First Part (Q.
XXX., A. 3), distinction is the cause of number.
Now things may be distinguished in two ways. First,
as those things that are altogether specifically dif-
ferent, e.g.) a horse and an ox. Secondly, as per-
fect and imperfect in the same species, e.g., a boy
and a man: and in this way the Divine law is divided
into Old and New. Hence the Apostle (Gal. iii. 24,
25) compares the state of man under the Old Law
to that of a child under a pedagogue; but the state
under the New Law, to that of a full grown man,
who is no longer under a pedagogue.
Now the perfection and imperfection of these two
laws is to be taken in connection with the three
conditions pertaining to law, as stated above. For,
in the first place, it belongs to law to be directed to
the common good as to its end, as stated above (Q.
XC., A. 2 ) . This good may be twofold. It may be a
sensible and earthly good; and to this, man was
directly ordained by the Old Law: wherefore, at the
very outset of the law, the people were invited to
the earthly kingdom of the Chananaeans (Exod. iii.
8, 17). Again it may be an intelligible and- heavenly
good: and to this, man is ordained by the New Law.
Wherefore, at the very beginning of His preaching,
Christ invited men to the kingdom of heaven, saying
(Matth. iv. 17) : Do penance, for the kingdom of
heaven is at hand. Hence Augustine says (Contra
OF THE VARIOUS KINDS OF LAW 25
Faust, iv.) that promises of temporal goods are con-
tained in the Old Testament, for which reason it is
called old; but the promise of eternal life belongs
to the New Testament.
Secondly, it belongs to the law to direct human
acts according to the order of righteousness (A. 4) :
wherein also the New Law surpasses the Old Law,
since it directs our internal acts, according to Matth.
v. 20: Unless your justice abound more than that of
the Scribes and Pharisees, you shall not enter into
the kingdom of heaven. Hence the saying that the
Old Law restrains the hand, but the New Law con-
trols the mind (3 Sentent., D. xl.).
Thirdly, it belongs to the law to induce men to
observe its commandments. This the Old Law did by
the fear of punishment: but the New Law, by love,
which is poured into our hearts by the grace of
Christ, bestowed in the New Law, but foreshadowed
in the Old. Hence Augustine says (Contra Adimant.
Manicb. disci p. xvii.) that there is little difference*
between the Law and the Gospel fear and love.
Reply Obj. i. As the father of a family issues
different commands to the children and to the adults,
so also the one King, God, in his one kingdom, gave
one law to men, while they were yet imperfect, and
another more perfect law, when, by the preceding
law, they had been led to a greater capacity for
Reply Obj. 2. The salvation of man could not be
* The little difference refers to the Latin words thttor and
amor, fear and love.
26 TREATISE ON LAW
achieved otherwise than through Christ, according to
Acts iv. 12: There is no other name . . . given to
-men, whereby we must be saved. Consequently the
law that brings all to salvation could not be given
until after the coming of Christ. But before His
coming it was necessary to give to the people, of
whom Christ was to be born, a law containing cer-
tain rudiments of righteousness unto salvation, in
order to prepare them to receive Him.
Reply Ob}. 3. The natural law directs man by way
of certain general precepts, common to both the per-
fect and the imperfect: wherefore it is one and the
same for all. But the Divine law directs man also in
certain particular matters, to which the perfect and
imperfect do not stand in the same relation. Hence
the necessity for the Divine law to be twofold, as
WHETHER THERE IS A LAW IN THE FOMES
We proceed thus to the Sixth Article:
Objection i . It would seem that there is no law of
the 'fomes' of sin. For Isidore says (Etym. v.) that
the law is based on reason. But the 'fomes' of sin is
not based on reason, but deviates from it. Therefore
the 'f omes* has not the nature of a law.
Obj. 2. Further, every law is binding, so that those
OF THE VARIOUS KINDS OF LAW 27
who do not obey it are called transgressors. But man
is not called a transgressor, from not following the
instigations of the 'fomes'; but rather from his
following them. Therefore the Domes' has not the
nature of a law.
Obj. 3. Further, the law is ordained to the com-
mon good, as stated above (Q. XC., A. 2). But the
'femes' inclines us, not to the common, but to our
own private good. Therefore the 'fomes' has not the
nature of sin.
On the contrary, The Apostle says (Rom. vii. 23) :
I see another law in my members, fighting against the
law of my mind.
I answer that, As stated above (A. 2; Q. XC., A.
i ad i ) , the law, as to its essence, resides in him that
rules and measures; but, by way of participation, in
that which is ruled and measured; so that every in-
clination or ordination which may be found in things
subject to the law, is called a law by participation, as
stated above (ibid.). Now those who are subject to
a law may receive a twofold inclination from the
lawgiver. First, in so far as he directly inclines his
subjects to something; sometimes indeed different sub-
jects to different acts; in this way we may say that
there is a military law and a mercantile law. Secondly,
indirectly; thus by the very fact that a lawgiver
deprives a subject of some dignity, the latter passes
into another order, so as to be under another law, as
it were: thus if a soldier be turned out of the army,
he becomes a subject of rural or of mercantile legisla-
28 TREATISE ON LAW
Accordingly under the Divine Lawgiver various
creatures have various natural inclinations, so that
what is, as it were, a law for one, is against the law
for another: thus I might say that fierceness is, in a
way, the law of a dog, but against the law of a sheep
or another meek animal. And so the law of man,
which, by the Divine ordinance, is alloted to him,
according to his proper natural condition, is that he
should act in accordance with reason: and this law
was so effective in the primitive state, that nothing
either beside or against reason could take man un-
awares. But when man turned his back on God, he
fell under the influence of his sensual impulses: in
fact this happens to each one individually, the more
he deviates from the path of reason, so that, after
a fashion, he is likened to the beasts that are led by
the impulse of sensuality, according to Ps. xlviii. 21:
Man, when he was in honour, did not understand:
he hath been compared to senseless beasts, and made
like to them.
So, then, this very inclination of sensuality which
is called the 'fomes,' in other animals has simply the
nature of a law, (yet only in so far as a law may be
said to be in such things), by reason of a direct
inclination. But in man, it has not the nature of law
in this way, rather is it a deviation from the law
of reason. But since, by the just sentence of God,
man is destitute of original justice, and his reason
bereft of its vigour, this impulse of sensuality,
whereby he is led, in so far as it is a penalty follow-
OF THE VARIOUS KINDS OF LAW 29
ing from the Divine law depriving man of his proper
dignity, has the nature of a law.
Reply Ob), i. This argument considers the *fomes'
in itself, as an incentive to evil. It is not thus that
it has the nature of a law, as stated above, but
according as it results from the justice of the Divine
law: it is as though we were to say that the law
allows a nobleman to be condemned to hard labour
for some misdeed.
Reply Ob]. 2. This argument considers law in the
light of a rule or measure: for it is in this sense that
those who deviate from the law become transgres-
sors. But the 'fomes' is not a law in this respect, but
by a kind of participation, as stated above.
Reply Ob}. 3. This argument considers the 'femes'
as to its proper inclination, and not as to its origin.
And yet if the inclination of sensuality be con-
sidered as it is in other animals, thus it is ordained
to the common good, namely, to the preservation of
nature in the species or in the individual. And this
is in man also, in so far as sensuality is subject to
reason. But it is called the 'femes' in so far as it
strays from the order of reason.
30 TREATISE ON LAW
OF THE EFFECTS OF LAW
(In Two Articles)
WE must now consider the effects of law; under
which head there are two points of inquiry: (i)
Whether an effect of law is to make men good? (2)
Whether the effects of law are to command, to for-
bid, to permit, and to punish, as the Jurist states?
WHETHER AN EFFECT OF LAW IS TO MAKE MEN GOOD?
We proceed thus to the First Article:
Objection i. It seems that it is not an effect of
law to make men good. For men are good through
virtue, since virtue, as stated in Ethic, ii. 6 is that
which makes its subject good. But virtue is in man
from God alone, because He it is Who works it in
us without us, as we stated above (Q. LV., A. 4)
in giving the definition of virtue. Therefore the law
does not make men good.
Qbj. 2. Further, Law does not profit a man unless
he obeys it. But the very fact that a man obeys a
law is due to his being good. Therefore in man good-
OF THE EFFECTS OF LAW 31
ness is presupposed to the law. Therefore the law does
not make men good.
Obj. 3. Further, Law is ordained to the common
good, as stated above (Q. XC., A. 2). But some be-
have well in things regarding the community, who
behave ill in things regarding themselves. Therefore
it is not the business of the law to make men good.
Ob}. 4. Further, some laws are tyrannical, as the
Philosopher says (Polit. iii. 6). But a tyrant does not
intend the good of his subjects, but considers only
his own profit. Therefore law does not make men-
On the contrary, The Philosopher says (Ethic, ii.
i) that the intention of every lawgiver is to make
I answer that, As stated above (Q. XC., A. i ad z;
AA. 3, 4), a law is nothing else than a dictate of
reason in the ruler by whom his subjects are governed.
Now the virtue of any subordinate thing consists in
its being well subordinated to that by which it is
regulated: thus we see that the virtue of the iras-
cible and concupiscible faculties consists in their
being obedient to reason; and accordingly the virtue
of every subject consists in his being well subjected
to his ruler, as the Philosopher says (Polit. i.). But
every law aims at being obeyed by those who are
subject to it. Consequently it is evident that the
proper effect of law is to lead its subjects to their
proper virtue: and since virtue is that which makes
its subject good, it follows that the proper effect of
law is to make those to whom it is given, good,
32 TREATISE ON LAW
either simply or in some particular respect. For if
the intention of the lawgiver is fixed on true good,
which is the common good regulated according to
Divine justice, it follows that the effect of the law is
to make men good simply. If, however, the intention
of the lawgiver is fixed on that which is not simply
good, but useful or pleasurable to himself, or in
opposition to Divine justice; then the law does not
make men good simply, but in respect to that particu-
lar government. In this way good is found even in
things that are bad of themselves: thus a man is
called a good robber, because he works in a way that
is adapted to his end.
Reply Obj. i. Virtue is twofold, as explained above
(Q. LXIIL, A. 2), viz., acquired and infused. Now
the fact of being accustomed to an action contrib-
utes to both, but in different ways; for it causes
the acquired virtue; while it disposes to infused virtue,
and preserves and fosters it when it already exists.
And since law is given for the purpose of directing
human acts; as far as human acts conduce to virtue,
so far does law make men good. Wherefore the
Philosopher says in the second book of the Politics
(Ethic, ii.) that lawgivers make -men good by habit-
uating them to good works.
Reply Obj. 2. It is not always through perfect
goodness of virtue that one obeys the law, but some-
times it is through fear of punishment, and some-
times from the mere dictate of reason, which is a
beginning of virtue, as stated above (Q. LXIIL, A.
OF THE EFFECTS OF LAW 33
Reply Obj. 3. The goodness of any part is con-
sidered in comparison with the whole; hence Au-
gustine says (Conf. iii.) that unseemly is the part
that harmonizes not with the whole. Since then every
man is a part of the state, it is impossible that a man
be good, unless he be well proportionate to the com-
mon good: nor can the whole be well consistent
unless its parts be proportionate to it. Consequently
the common good of the state cannot flourish, unless
the citizens be virtuous, at least those whose business
it is to govern. But it is enough for the good of the
community, that the other citizens be so far virtuous
that they obey the commands of their rulers. Hence
the Philosopher says (Pol it. iii. 2) that the virtue of
a sovereign is the same as that of a good man y but
the virtue of any common citizen is not the same as
that of a good man.
Reply Obj. 4. A tyrannical law, through not being
according to reason, is not a law, absolutely speaking,
but rather a perversion of law; and yet in so far as it
is something in the nature of a law, it aims at the
citizens being good. For all it has in the nature of a
law consists in its being an ordinance made by a
superior to his subjects, and aims at being obeyed by
them, which is to make them good, not simply, but
with respect to that particular government.
34 TREATISE ON LAW
WHETHER THE ACTS OF LAW ARE SUITABLY
We proceed thus to the Second Article:
Objection i. It would seem that the acts of law
are not suitably assigned as consisting in command,
prohibition, permission and punishment. For every
law is a general precept, as the jurist states (ibid.)
But command and precept are the same. Therefore
the other three are superfluous.
Obj. 2. Further, the effect of a law is to induce its
subjects to be good, as stated above (A. i). But
counsel aims at a higher good than a command does.
Therefore it belongs to law to counsel rather than
Obj. 3. Further, just as punishment stirs a man to
good deeds, so does reward. Therefore if to punish
is reckoned an effect of law, so also is to reward.
Obj. 4. Further, the intention of a lawgiver is to
make men good, as stated above (A. i ) . But he that
obeys the law, merely through fear of being punished,
is not good: because although a good deed may be
done through servile fear, i.e., fear of punishment, it
is not done well, as Augustine says (Contra duas
Epist. Pelag. ii.) . Therefore punishment is not a proper
effect of law.
On the contrary, Isidore says (Etym. v. 19) : Every
OF THE EFFECTS OF LAW 35
law either permits something, as: ( A brave man may
demand his reward 3 : or forbids something, as: 'No
man may ask a consecrated virgin in marriage 9 : or
punishes, as: f Let him that commits a murder be put
to death. 9
I answer that, Just as an assertion is a dictate of
reason asserting something, so is a law a dictate of
reason, commanding something. Now it is proper to
reason to lead from one thing to another. Wherefore
just as, in demonstrative sciences, the reason leads us
from certain principles to assent to the conclusion,
so it induces us by some means to assent to the pre-
cept of the law.
Now the precepts of law are concerned with hu-
man acts, in which the law directs, as stated above
(Q. XC, AA. i, 2; Q. XCL, A. 4). Again, there
are three kinds of human acts: for, as stated above
(Q. XVIIL, A. 8), some acts are good generically,
viz., acts of virtue; and in respect of these the
act of the law is a precept or command, for the law
commands all acts of virtue (Ethic, v. i). Some acts
are evil generically, viz., acts of vice, and in respect
of these the law forbids. Some acts are generically
indifferent, and in respect of these the law permits;
and all acts that are either not distinctly good or not
distinctly bad may be called indifferent. And it is
the fear of punishment that law makes use of in
order to ensure obedience: in which respect punish-
ment is an effect of law.
Reply Obj. i. Just as to cease from evil is a kind
of good, so a prohibition is a kind of precept: and
3 6 TREATISE ON LAW
accordingly, taking precept in a wide sense, every
law is a kind of precept.
Reply Obj. 2. To advise is not a proper act of law,
but may be within the competency even of a private
person, who cannot make a law. Wherefore too the
Apostle, after giving a certain counsel (i Cor. vii.
12) says: I speak, not the Lord. Consequently it is
not reckoned as an effect of law.
Reply Obj. 3. To reward may also pertain to any-
one: but to punish pertains to none but the framer of
the law, by whose authority the pain is inflicted.
Wherefore to reward is not reckoned an effect of law,
but only to punish.
Reply Obj. 4. From becoming accustomed to avoid
evil and fulfil what is good, through fear of punish-
ment, one is sometimes led on to do so likewise, with
delight and of one's own accord. Accordingly, law,
even by punishing, leads men on to being good.
OF THE ETERNAL LAW
(In Six Articles)
WE must now consider each law by itself; and (i)
The eternal law: (2) The natural law: (3) The
human law: (4) The old law: (5) The new law,
which is the law of the Gospel. Of the sixth law
which is the law of the 'fomes,' suffice what we have
said when treating of original sin.
OF THE ETERNAL LAW 37
Concerning the first there are six points o in-
quiry: (i) What is the eternal law? (2) Whether it
is known to all? (3) Whether every law is derived
from it? (4) Whether necessary things are subject
to the eternal law? (5) Whether natural contingen-
cies are subject to the eternal law? (6) Whether all
human things are subject to it?
WHETHER THE ETERNAL LAW IS A SOVEREIGN TYPE*
EXISTING IN GOD?
We proceed thus to the First Article:
Objection i. It would seem that the eternal law
is not a sovereign type existing in God. For there is
only one eternal law. But there are many types of
things in the Divine mind; for Augustine says (Q#.
Ixxxiii., qu. 46) that God made each thing according
to its type. Therefore the eternal law does not seem
to be a type existing in the Divine mind.
Obj. 2. Further, it is essential to a law that it be
promulgated by word, as stated above (Q. XQ, A.
4) . But Word is a Personal name in God, as stated in
the First Part (Q. XXXIV., A. i): whereas type
refers to the Essence. Therefore the eternal law is not
the same as a Divine type.
Ob}. 3. Further, Augustine says (De Vera Relig.
xxx.) : We see a law above our minds, which is
38 TREATISE ON LAW
called truth. But the law which is above our minds
is the eternal law. Therefore truth is the eternal law.
But the idea of truth is not the same as the idea of
a type. Therefore the eternal law is not the same as
the sovereign type.
On the contrary, Augustine says (De Lib. Arb. i.
6) that the eternal law is the sovereign type, to
which we must always conform.
1 ansiver that, Just as in every artificer there pre-
exists a type of the things that are made by his art,
so too in every governor there must pre-exist the type
of the order of those things that are to be done by
those who are subject to his government. And just
as the type of the things yet to be made by an art is
called the art or exemplar of the products of that
art, so too the type in him who governs the acts of
his subjects, bears the character of a law, provided
the other conditions be present which we have men-
tioned above (Q. XC.). Now God, by His wisdom,
is the Creator of all things, in relation to which He
stands as the artificer to the products of his art, as
stated in the First Part (Q. XIV., A. 8). Moreover
He governs all the acts and movements that are to
be found in each single creature, as was also stated
in the First Part (Q. GUI., A. 5). Wherefore as the
type of the Divine Wisdom, inasmuch as by It all
things are created, has the character of art, exemplar
or idea; so the type of Divine Wisdom, as moving all
things to their due end, bears the character of law.
Accordingly the eternal law is nothing else than the
OF THE ETERNAL LAW 39
type of Divine Wisdom, as directing all actions and
Reply Obj. i. Augustine is speaking in that passage
of the ideal types which regard the proper nature of
each single thing; and consequently in them there is
a certain distinction and plurality, according to their
different relations to things, as stated in the First
Part (Q. XV., A. 2). But law is said to direct hu-
man acts by ordaining them to the common good,
as stated above (Q. XC., A. 2). And things, which
are in themselves different, may be considered as one,
according as they are ordained to one common thing.
Wherefore the eternal law is one since it is the type
of this order.
Reply Obj. 2. With regard to any sort of word,
two points may be considered: viz., the word itself,
and that which is expressed by the word. For the
spoken word is something uttered by the mouth of
man, and expresses that which is signified by the
human word. The same applies to the human mental
word, which is nothing else than something conceived
by the mind, by which man expresses his thoughts
mentally. So then in God the Word conceived by the
intellect of the Father is the name of a Person: but
all things that are in the Father's knowledge, whether
they refer to the Essence or to the Persons, or to the
works of God, are expressed by this Word, as Au-
gustine declares (De Trin. xv. 14) . And among other
things expressed by this Word, the eternal law itself
is expressed thereby. Nor does it follow that the
40 TREATISE ON LAW
eternal law is a Personal name in God: yet it is
appropriated to the Son, on account of the kinship
between type and word.
Reply Ob]. 3. The types of the Divine intellect do
not stand in the same relation to things, as the types
of the human intellect. For the human intellect is
measured by things, so that a human concept is not
true by reason of itself, but by reason of its being
consonant with things, since an opinion is true or
false according as it ansivers to the reality. But the
Divine intellect is the measure of things: since each
thing has so far truth in it, as it represents the
Divine intellect, as was stated in the First Part (Q.
XVI., A. i). Consequently the Divine intellect is
true in itself; and its type is truth itself.
WHETHER THE ETERNAL LAW IS KNOWN TO ALL?
We proceed thus to the Second Article:
Objection i. It would seem that the eternal law
is not known to all. Because, as the Apostle says (i
Cor. ii. n), the things that are of God no man
knowethy but the Spirit of God. But the eternal law
is a type existing in the Divine mind. Therefore it
is unknown to all save God alone.
Ob}. 2. Further, as Augustine says (De Lib. Arb.
i. 6) the eternal law is that by which it is right that
all things should be most orderly. But all do not
OF THE ETERNAL LAW 41
know how all things are most orderly. Therefore all
do not know the eternal law.
Ob}. 3. Further, Augustine says (De Vera Relig.
xxxi.) that the eternal law is not subject to the
judgment of man. But according to Ethic, i. any man
can jiidge well of what he knows. Therefore the
eternal law is not known to us.
On the contrary } Augustine says (De Lib. Arb. i.
6) that knowledge of the eternal law is imprinted on
I answer that, A thing may be known in two ways:
first, in itself; secondly, in its effect, wherein some
likeness of that thing is found: thus someone not
seeing the sun in its substance, may know it by its
rays. So then no one can know the eternal law, as it
is in itself, except the blessed who see God in His
Essence. But every rational creature knows it in its
reflection, greater or less. For every knowledge of
truth is a kind of reflection and participation of the
eternal law, which is the unchangeable truth, as
Augustine says (De Vera Relig. xxxi.). Now all men
know the truth to a certain extent, at least as to
the common principles of the natural law: and as to
the others, they partake of the knowledge of truth,
some more, some less; and in this respect are more or
less cognizant of the eternal law.
Reply Obj. i. We cannot know the things that are
of God, as they are in themselves; but they are made
known to us in their effects, according to Rom. i.
20: The invisible things of God . . . a re clearly seen,
being understood by the things that are made.
42 TREATISE ON LAW
Reply Obj. 2. Although each one knows the eternal
law according to his own capacity, in the way ex-
plained above, yet none can comprehend it: for it
cannot be made perfectly known by its effects.
Therefore it does not follow that anyone who knows
the eternal law in the way aforesaid, knows also
the whole order of things, whereby they are most
Reply Ob}. 3. To judge of a thing may be under-
stood in two ways. First, as when a cognitive power
judges of its proper object, according to Job xii. n:
Doth not the ear discern words, and the palate of
him that eateth, the taste? It is to this kind of
judgment that the Philosopher alludes when he says
that anyone can judge well of what he knows, by
judging, namely, whether what is put forward is true.
In another way we speak of a superior judging of a
subordinate by a kind of practical judgment, as to
whether he should be such and such or not. And thus
none can judge of the eternal law.
WHETHER EVERY LAW IS DERIVED FROM THE
We proceed thus to the Third Article:
Objection i. It would seem that not every law is
derived from the eternal law. For there is a law of
the 'fomes,' as stated above (Q. XCL, A. 6), which
OF THE ETERNAL LAW 43
is not derived from that Divine law which is the
eternal law, since thereunto pertains the prudence of
the flesh) of which the Apostle says (Rom. viii. 7),
that it cannot be subject to the laiv of God. There-
fore not every law is derived from the eternal law.
Obj. 2. Further, nothing unjust can be derived
from the external law, because, as stated above (A.
2, Obj. 2), the eternal laiv is that, according to
which it is right that all things should be most
orderly. But some laws are unjust, according to Isa.
x. i : Woe to them that make wicked laws. Therefore
not every law is derived from the eternal law.
Obj. 3. Further, Augustine says (De Lib. Arb.
i. 5) that the law which is framed for ruling the
people, rightly permits many things which are pun-
ished by Divine providence. But the type of Divine
providence is the eternal law, as stated above (A. i).
Therefore not even every good law is derived from
the eternal law.
On the contrary, Divine Wisdom says (Prov. viii.
15): By Me kings reign, and lawgivers decree just
things. But the type of Divine Wisdom is the eternal
law, as stated above (A. i). Therefore all laws pro-
ceed from the eternal law.
/ answer that, As stated above (Q. XC., A A. i,
2), law denotes a kind of plan directing acts towards
an end. Now wherever there are movers ordained to
one another, the power of the second mover must
needs be derived from the power of the first mover;
since the second mover does not move except in so
far as it is moved by the first. Wherefore we observe
44 TREATISE ON LAW
the same in all those who govern, so that the plan
of government is derived by secondary governors
from the governor in chief: thus the plan of what
is to be done in a state flows from the king's com-
mand to his inferior administrators: and again in
things of art the plan of whatever is to be done by
art flows from the chief craftsman to the under-
craftsmen who work with their hands. Since then
the eternal law is the plan of government in the Chief
Governor, all the plans of government in the inferior
governors must be derived from the eternal law. But
these plans of inferior governors are all other laws
besides the eternal law. Therefore all laws, in so far
as they partake of right reason, are derived from the
eternal law. Hence Augustine says (De Lib. Arb. i.
6) that in temporal law there is nothing just and
lawful, but what man has drawn from the eternal
Reply Ob}, i. The 'fomes* has the nature of law
in man, in so far as it is a punishment resulting from
Divine justice; and in this respect it is evident that
it is derived from the eternal law. But 'in so far as it
denotes a proneness to sin, it is contrary to the Divine
law, and has not the nature of law, as stated above
(Q. XCL, A. 6).
Reply Obj. 2. Human law has the nature of law
in so far as it partakes of right reason; and it is
clear that, in this respect, it is derived from the
eternal law. But in so far as it deviates from reason,
it is called an unjust law, and has the nature, not
of law but of violence. Nevertheless even an unjust
OF THE ETERNAL LAW 45
law, in so far as it retains some appearance of law,
though being framed by one who is in power, is
derived from the eternal law; since all power is from
the Lord God, according to Rom. xiii. i.
Reply Obj. 3. Human law is said to permit certain
things, not as approving of them, but as being un-
able to direct them. And many things are directed
by the Divine law, which human law is unable to
direct, because more things are subject to a higher
than to a lower cause. Hence the very fact that
human law does not meddle with matters it cannot
direct, comes under the ordination of the eternal law.
It would be different, were human law to sanction
what the eternal law condemns. Consequently it does
not follow that human law is not derived from the
eternal law, but that it is not on a perfect equality
WHETHER NECESSARY AND ETERNAL THINGS ARE
SUBJECT TO THE ETERNAL LAW?
We proceed thus to the fourth Article:
Objection i. It would seem that necessary and
eternal things are subject to the eternal law. For
whatever is reasonable is subject to reason. But the
Divine will is reasonable, for it is just. Therefore it
is subject to (the Divine) reason. But the eternal law
is the Divine reason. Therefore God's will is sub-
4$ TREATISE ON LAW
ject to the eternal law. But God's will is eternal.
Therefore eternal and necessary things are subject to
the eternal law.
Ob). 2. Further, whatever is subject to the King,
is subject to the King's law. Now the Son, according
to i Cor. xv. 28, 24, shall be subject . . . to God and
the Father) . . . when He shall have delivered up the
Kingdom to Him. Therefore the Son, Who is eternal,
is subject to the eternal law.
Ob). 3. Further, the eternal law is Divine provi-
dence as a type. But many necessary things are sub-
ject to Divine providence: for instance, the stability
of incorporeal substances and of the heavenly bodies.
Therefore even necessary things are subject to the
On the contrary) Things that are necessary cannot
be otherwise, and consequently need no restraining.
But laws are imposed on men, in order to restrain
them from evil, as explained above (Q. XCIL, A.
2). Therefore necessary things are not subject to the
I answer that. As stated above (A. i), the eternal
law is the type of the Divine government. Con-
sequently whatever is subject to the Divine govern-
ment, is subject to the eternal law: while if anything
is not subject to the Divine government, neither is it
subject to the eternal law. The application of this
distinction may be gathered by looking around us.
For those things are subject to human government,
which can be done by man; but what pertains to the
nature of man is not subject to human government;
OF THE ETERNAL LAW 47
for instance, that he should have a soul, hands, or
feet. Accordingly all that is in things created by
God, whether it be contingent or necessary, is subject
to the eternal law: while things pertaining to the
Divine Nature or Essence are not subject to the
eternal law, but are the eternal law itself.
Reply Obj. i. We may speak of God's will in two
ways. First, as to the will itself: and thus, since God's
will is His very Essence, it is subject neither to the
Divine government, nor to the eternal law, but is
the same thing as the eternal law. Secondly, we may
speak of God's will, as to the things themselves that
God wills about creatures; which things are subject
to the eternal law, in so far as they are planned by
Divine Wisdom. In reference to these things God's
will is said to be reasonable (rationalis) : though re-
garded in itself it should rather be called their type
Reply Obj. 2. God the Son was not made by God,
but was naturally born of God. Consequently He is
not subject to Divine providence or to the eternal
law: but rather is Himself the eternal law by a kind
of appropriation, as Augustine explains (De Vera
Relig. xxxi.). But He is said to be subject to the
Father by reason of His human nature, in respect of
which also the Father is said to be greater than He.
The third objection we grant, because it deals with
those necessary things that are created.
Reply Obj. 4. As the Philosopher says (Metaph. v.,
text. 6), some necessary things have a cause of their
necessity: and thus they derive from something else
48 TREATISE ON LAW
the fact that they cannot be otherwise. And this is
in itself a most effective restraint; for whatever is
restrained, is said to be restrained in so far as it cannot
do otherwise than it is allowed to.
WHETHER NATURAL CONTINGENTS ARE SUBJECT
TO THE ETERNAL LAW?
We proceed thus to the Fifth Article:
Objection i. It would seem that natural contin-
gents are not subject to the eternal law. Because pro-
mulgation is essential to law, as stated above (Q. XC.,
A. 4). But a law cannot be promulgated except to
rational creatures, to whom it is possible to make an
announcement. Therefore none but rational creatures
are subject to the eternal law; and consequently na-
tural contingents are not.
Ob}. 2. Further, "Whatever obeys reason partakes
somewhat of reason, as stated in Ethic, i. But the
eternal law is the supreme type, as stated above (A.
i ) . Since then natural contingents do not partake of
reason in any way, but are altogether void of reason,
it seems that they are not subject to the eternal law.
Ob}. 3. Further, the eternal law is most efficient.
But in natural contingents defects occur. Therefore
they are not subject to the eternal law.
On the contrary 9 It is written (Prov. viii. 29):
When He compassed the sea with its bounds, and set
OF THE ETERNAL LAW 49
a law to the waters, that they should not pass their
I answer that, We must speak otherwise of the law
of man, than of the eternal law which is the law of
God. For the law of man extends only to rational
creatures subject to man. The reason of this is because
law directs the actions of those that are subject to
the government of someone; wherefore, properly
speaking, none imposes a law on his own actions.
Now whatever is done regarding the use of irrational
things subject to man, is done by the act of man
himself moving those things, for these irrational crea-
tures do not move themselves, but are moved by
others, as stated above (Q. I., A. 2). Consequently
man cannot impose laws on irrational beings, how-
ever much they may be subject to him. But he can
impose laws on rational beings subject to him, in so
far as by his command or pronouncement of any
kind, he imprints on their minds a rule which is a
principle of action.
Now just as man, by such pronouncements, im-
presses a kind of inward principle of action on the
man that is subject to him, so God imprints on the
whole of nature the principles of its proper actions.
And so, in this way, God is said to command the
whole of nature, according to Ps. cxlviii. 6: He hath
made a decree, and it shall not pass away. And thus
all actions and movements of the whole of nature are
subject to the eternal law. Consequently irrational
creatures are subject to the eternal law, through
being moved by Divine providence; but not, as ra-
50 TREATISE ON LAW
tional creatures are, through understanding the
Reply Ofy. i. The impression of an inward active
principle is to natural things, what the promulgation
of law is to men: because law, by being promulgated,
imprints on man a directive principle of human
actions, as stated above.
Reply Ob}. 2. Irrational creatures neither partake
of nor are obedient to human reason: whereas they do
partake of the Divine Reason by obeying it; because
the power of Divine Reason extends over more things
than human reason does. And as the members of the
human body are moved at the command of reason,
and yet do not partake of reason, since they have no
apprehension subordinate to reason; so too irrational
creatures are moved by God, without, on that ac-
count, being rational.
Reply Obj. 3. Although the defects which occur
in natural things are outside the order of particular
causes, they are not outside the order of universal
causes, especially of the First Cause, i.e., God, from
Whose providence nothing can escape, as stated in
the First Part (Q. XXII., A. 2). And since the
eternal law is the type of Divine providence, as stated
above (A. i), hence the defects of natural things are
subject to the eternal law.
OF THE ETERNAL LAW 51
WHETHER ALL HUMAN AFFAIRS ARE SUBJECT
TO THE ETERNAL LAW?
We proceed thus to the Sixth Article:
Objection i. It would seem that not all human
affairs are subject to the eternal law. For the Apostle
says (Gal. v. 18): If you are led by the spirit you
are not under the law. But the righteous who are the
sons of God by adoption, are led by the spirit of God,
according to Rom. viii. 14: Whosoever are led by
the Spirit of God, they are the sons of God. Therefore
not all men are under the eternal law.
Ob}. 2. Further, the Apostle says (Rom. viii. 7) :
The prudence (Vulg., wisdom) of the flesh is an
enemy to God: for it is not subject to the law of
God. But many are those in whom the prudence of
the flesh dominates. Therefore all men are not sub-
ject to the eternal law which is the law of God.
Ob}. 3. Further, Augustine says (De Lib. Arb. i. 6)
that the eternal law is that by which the wicked
deserve misery, the good, a life of blessedness. But
those who are already blessed, and those who are al-
ready lost, are not in the state of merit. Therefore
they are not under the eternal law.
On the contrary, Augustine says (De Civ. Dei, xix.
12) : Nothing evades the laws of the most high Crea-
tor and Governor, for by Him the peace of the uni-
verse is administered.
52 TREATISE ON LAW
I ansiver that, There are two ways in which a
thing is subject to the eternal law, as explained above
(A. 5 ) : first, by partaking of the eternal law by way
of knowledge; secondly, by way of action and pas-
sion, i.e., by partaking of the eternal law by way of
an inward motive principle: and in this second way,
irrational creatures are subject to the eternal law, as
stated above (ibid.). But since the rational nature,
together with that which it has in common with all
creatures, has something proper to itself inasmuch as
it is rational, consequently it is subject to the eternal
law in both ways; because while each rational crea-
ture has some knowledge of the eternal law, as stated
above (A. 2 ) , it also has a natural inclination to that
which is in harmony with the eternal law; for we are
naturally adapted to be the recipients of virtue
(Ethic, ii. i).
Both ways, however, are imperfect, and to a certain
extent destroyed, in the wicked; because in them the
natural inclination to virtue is corrupted by vicious
habits, and, moreover, the natural knowledge of good
is darkened by passions and habits of sin. But in the
good both ways are found more perfect: because in
them, besides the natural knowledge of good, there
is the added knowledge of faith and wisdom; and
again, besides the natural inclination to good, there
is the added interior motive of grace and virtue.
Accordingly, the good are perfectly subject to the
eternal law, as always acting according to it: whereas
the wicked are subject to the eternal law, imperfectly
as to their actions, indeed, since both their knowledge
OF THE ETERNAL LAW 53
of good, and their inclination thereto, are imperfect:
but this imperfection on the part of action is supplied
on the part of passion, in so far as they suffer what
the eternal law decrees concerning them, according as
they fail to act in harmony with that law. Hence
Augustine says (De Lib. Arb. i. i5): 7 esteem that
the righteous act according to the eternal law; and
(De Catech. Rud. xviii.) : Out of the just mhery of
the souls which deserted Mm, God knew how to fur-
nish the inferior parts of His creation with most
Reply Obj. i. This saying of the Apostle may be
understood in two ways. First, so that a man is said
to be under the law, through being pinned down
thereby, against his will, as by a load. Hence, on the
same passage a gloss says that he is under the law,
who refrains fram evil deeds, through fear of the
pimishment threatened by the law, and not from love
of virtue. In this way the spiritual man is not under
the law, because he fulfils the law willingly, through
charity which is poured into his heart by the Holy
Ghost. Secondly, it can be understood as meaning that
the works of a man, who is led by the Holy Ghost,
are the works of the Holy Ghost rather than his own.
Therefore, since the Holy Ghost is not under the law,
as neither is the Son, as stated above (A. 4 ad 2) ; it
follows that such works, in so far as they are of the
Holy Ghost, are not under the law. The Apostle
witnesses to this when he says (2 Cor. iii. 17) : Where
the Spirit of the Lord is, there is liberty.
Reply Ob}. 2. The prudence of the flesh cannot be
54 TREATISE ON LAW
subject to the law of God as regards action; since it
inclines to actions contrary to the Divine law: yet
it is subject to the law of God, as regards passion;
since it deserves to suffer punishment according to
the law of Divine justice. Nevertheless in no man
does the prudence of the flesh dominate so far as to
destroy the whole good of his nature; and con-
sequently there remains in man the inclination to act
in accordance with the eternal law. For we have seen
above (Q. LXXXV., A. 2) that sin does not destroy
entirely the good of nature.
Reply Obj. 3. A thing is maintained in the end
and moved towards the end by one and the same
cause: thus gravity which makes a heavy body rest
in the lower place is also the cause of its being moved
thither. "We therefore reply that as it is according to
the eternal law that some deserve happiness, others
unhappiness, so it is by the eternal law that some are
maintained in a happy state, others in an unhappy
state. Accordingly both the blessed and the damned
are under the eternal law.
OF THE NATURAL LAW
(In Six Articles)
must now consider the natural law; concerning
which there are six points of inquiry: (r) What is
OF THE NATURAL LAW 55
the natural law? (2) What are the precepts of the
natural law? (3) Whether all acts of virtue are pre-
scribed by the natural law? (4) Whether the natural
law is the same in all? (5) Whether it is changeable?
(6) Whether it can be abolished from the heart of
WHETHER THE NATURAL LAW IS A HABIT?
We proceed thus to the First Article:
Objection i. It would seem that the natural law
is a habit. Because, as the Philosopher says (Ethic.
ii. 5 ) , there are three things in the soul, power, habit,
and passion. But the natural law is not one of the
soul's powers: nor is it one of the passions; as we may
see by going through them one by one. Therefore the
natural law is a habit.
Obj. 2. Further, Basil says that the conscience or
synderesis is the law of our mind; which can only
apply to the natural law. But the synderesis is a habit,
as was shown in the First Part (Q. LXXIX., A. 12).
Therefore the natural law is a habit.
Ob}. 3. Further, the natural law abides in man al-
ways, as will be shown further on (A. 6). But man's
reason, which the law regards, does not always think
about the natural law. Therefore the natural law is
not an act, but a habit.
On the contrary, Augustine says (De Bono Conjug.
5 6 TREATISE ON LAW
xxi) that a habit ;s that whereby something is done
when necessary. But such is not the natural law: since
it is in infants and in the damned who cannot
act by it. Therefore the natural law is not a habit.
I aimvcr that, A thing may be called a habit in
two ways. First, properly and essentially: and thus the
natural law is not a habit. For it has been stated
above (Q. XC., A. i ad 2) that the natural law is
something appointed by reason, just as a proposition
is a work of reason. Now that which a man does is not
the same as that whereby he does it: for he makes a
becoming speech by the habit of grammar. Since then
a habit is that by which we act, a law cannot be a
habit properly and essentially.
Secondly, the term habit may be applied to that
which we hold by a habit: thus faith may mean that
which we hold by faith. And accordingly, since the
precepts of the natural law are sometimes considered
by reason actually, while sometimes they are in the
reason only habitually, in this way the natural law
may be called a habit. Thus, in speculative matters,
the indemonstrable principles are not the habit itself
whereby we hold those principles, but are the princi-
ples the habit of which we possess.
Reply Qb). r. The Philosopher proposes there to
discover the genus of virtue; and since it is evident
that virtue is a principle of action, he mentions only
those things which are principles of human acts, viz.,
powers, habits and passions. But there are other things
in the soul besides these three: there are acts; thus to
will is in the one that wills; again, things known are
OF THE NATURAL LAW 57
in the knower; moreover its own natural properties
are in the soul, such as immortality and the like.
Reply Ob}. 2. Synderesis is said to be the law of
our mind, because it is a habit containing the precepts
of the natural law, which are the first principles of
Reply Obj. 3. This argument proves that the nat-
ural law is held habitually: and this is granted.
To the argument advanced in the contrary sense
we reply that sometimes a man is unable to make use
of that which is in him habitually, on account of
some impediment; thus, on account of sleep, a man
is unable to use the habit of science. In like manner,
through the deficiency of his age, a child cannot use
the habit of understanding of principles, or the nat-
ural law, which is in him habitually.
WHETHER THE NATURAL LAW CONTAINS SEVERAL
PRECEPTS, OR ONE ONLY?
We proceed thus to the Second Article:
Objection i. It would seem that the natural law
contains, not several precepts, but one only. For law
is a kind of precept, as stated above (Q. XCIL, A.
2). If therefore there were many precepts of the
natural law, it would follow that there are also many
Obj. 2. Further, the natural law is consequent to
58 TREATISE ON LAW
human nature. But human nature, as a whole, is one;
though, as to its parts, it is manifold. Therefore,
either there is but one precept of the law of nature,
on account of the unity of nature as a whole; or
there are many, by reason of the number of parts of
human nature. The result would be that even things
relating to the inclination of the concupiscible faculty
belong to the natural law.
Obj. 3. Further, law is something pertaining to
reason, as stated above (Q. XC., A. i). Now reason
is but one in man. Therefore there is only one precept
of the natural law.
On the contrary } The precepts of the natural law
in man stand in relation to practical matters, as the
first principles to matters of demonstration. But there
are several first indemonstrable principles. Therefore
there are also several precepts of the natural law.
I answer that, As stated above (Q. XCL, A. 3),
the precepts of the natural law are to the practical
reason, what the first principles of demonstrations
are to the speculative reason; because both are self-
evident principles. Now a thing is said to be self-
evident in two ways: first, in itself; secondly, in re-
lation to us. Any proposition is said to be self-evident
in itself, if its predicate is contained in the notion of
the subject: although, to one who knows not the
definition of the subject, it happens that such a
proposition is not self-evident. For instance, this
proposition, Man is a rational being, is, in its very
nature, self-evident, since who says man, says a ra-
tional being: and yet to one who knows not what a
OF THE NATURAL LAW 59
man is, this proposition is not self-evident. Hence it
is that, as Boethius says (De Hebdom.), certain
axioms or propositions are universally self-evident to
all; and such are those propositions whose terms are
known to all, as, Every whole is greater than its part,
and, Things equal to one and the same are equal to
one another. But some propositions are self-evident
only to the wise, who understand the meaning of the
terms of such propositions: thus to one who under-
stands that an angel is not a body, it is self-evident
that an angel is not circumscriptively in a place: but
this is not evident to the unlearned, for they cannot
Now a certain order is to be found in those things
that are apprehended universally. For that which, be-
fore aught else, falls under apprehension, is being, the
notion of which is included in all things whatsoever
a man apprehends. Wherefore the first indemonstrable
principle is that the same thing cannot be affirmed
and denied at the same time, which is based on the
notion of being and not-being: and on this principle
all others are based, as is stated in Metapb. iv., text.
9. Now as being is the first thing that falls under
the apprehension simply, so good is the first thing
that falls under the apprehension of the practical
reason, which is directed to action: since every agent
acts for an end under the aspect of good. Conse-
quently the first principle in the practical reason is
one founded on the notion of good, viz., that good is
that which all things seek after. Hence this is the
first precept of law, that good is to be done and en-
60 TREATISE ON LAW
sued, and evil Is to be avoided. All other precepts of
the natural law are based upon this: so that whatever
the practical reason naturally apprehends as man's
good (or evil) belongs to the precepts of the natural
law as something to be done or avoided.
Since, however, good has the nature of an end, and
evil, the nature of a contrary, hence it is that all
those things to which man has a natural inclination,
are naturally apprehended by reason as being good,
and consequently as objects of pursuit, and their con-
traries as evil, and objects of avoidance. Wherefore
according to the order of natural inclinations, is the
order of the precepts of the natural law. Because in
man there is first of all an inclination to good in ac-
cordance with the nature which he has in common
with all substances: inasmuch as every substance seeks
the preservation of its own being, according to its
nature: and by reason of this inclination, whatever
is a means of preserving human life, and of warding
off its obstacles, belongs to the natural law. Secondly,
there is in man an inclination to things that pertain to
him more specially, according to that nature which
he has in common with other animals: and in virtue
of this inclination, those things are said to belong to
the natural law, which nature has taught to all ani-
mals* such as sexual intercourse, education of off-
spring and so forth. Thirdly, there is in man an in-
clination to good, according to the nature of his rea-
son, which nature is proper to him: thus man has a
natural inclination to know the truth about God, and
OF THE NATURAL LAW 6 1
to live in society: and in this respect, whatever per-
tains to this inclination belongs to the natural law;
for instance, to shun ignorance, to avoid offending
those among whom one has to live, and other such
things regarding the above inclination.
Reply Ob}, i. All these precepts of the law of nature
have the character of one natural law, inasmuch as
they flow from one first precept.
Reply Obj. 2. All the inclinations of any parts what-
soever of human nature, e.g., of the concupiscible
and irascible parts, in so far as they are ruled by rea-
son, belong to the natural law, and are reduced to one
first precept, as stated above: so that the precepts of
the natural law are many in themselves, but are based
on one common foundation.
Reply Obj. 3. Although reason is one in itself, yet
it directs all things regarding man; so that whatever
can be ruled by reason, is contained under the law of
WHETHER ALL ACTS OF VIRTUE ARE PRESCRIBED
BY THE NATURAL LAW?
We proceed thus to the Third Article:
Objection i. It would seem that not all acts of
virtue are prescribed by the natural law. Because, as
stated above (Q. XC., A. 2) it is essential to a law
that it be ordained to the common good. But some
6 2 TREATISE ON LAW
acts of virtue are ordained to the private good of the
individual, as is evident especially in regard to acts
of temperance. Therefore not all acts of virtue are
the subject of natural law.
Ob}. 2. Further, every sin is opposed to some vir-
tuous act. If therefore all acts of virtue are pre-
scribed by the natural law, it seems to follow that all
sins are against nature: whereas this applies to certain
Ob}. 3. Further, those things which are according
to nature are common to all. But acts of virtue are
not common to all: since a thing is virtuous in one,
and vicious in another. Therefore not all acts of vir-
tue are prescribed by the natural law.
On the contrary, Damascene says (De Fide Or-
thod. iii. 4) that virtues are natural. Therefore vir-
tuous acts also are a subject of the natural law.
I answer that, We may speak of virtuous acts in
two ways: first, under the aspect of virtuous; sec-
ondly, as such and such acts considered in their
proper species. If then we speak of acts of virtue,
considered as virtuous, thus all virtuous acts belong
to the natural law. For it has been stated (A. 2) that
to the natural law belongs everything to which a
man is inclined according to his nature. Now each
thing is inclined naturally to an operation that is
suitable to it according to its form: thus fire is in-
clined to give heat. Wherefore, since the rational soul
is the proper form of man, there is in every man a
natural inclination to act according to reason: and
this is to act according to virtue. Consequently, con-
OF THE NATURAL LAW 63
sidered thus, all acts of virtue are prescribed by the
natural law: since each one's reason naturally dic-
tates to him to act virtuously. But if we speak of
virtuous acts, considered in themselves, i.e., in their
proper species, thus not all virtuous acts are pre-
scribed by the natural law: for many things are done
virtuously, to which nature does not incline at first;
but which, through the inquiry of reason, have been
found by men to be conducive to well-living.
Reply Ob), i. Temperance is about the natural
concupiscenses of food, drink and sexual matters,
which are indeed ordained to the natural common
good, just as other matters of law are ordained to the
moral common good.
Reply Obj. 2. By human nature we may mean
either that which is proper to man and in this sense
all sins, as being against reason, are also against na-
ture, as Damascene states (De Fide Or t bod. ii. 30) :
or we may mean that nature which is common to
man and other animals; and in this sense, certain
special sins are said to be against nature; thus con-
trary to sexual intercourse, which is natural to all
animals, is unisexual lust, which has received the
special name of the unnatural crime.
Reply Obj. 3. This argument considers acts in
themselves. For it is owing to the various conditions
of men, that certain acts are virtuous for some, as
being proportionate and becoming to them, while
they are vicious for others, as being out of propor-
tion to them.
64 TREATISE ON LAW
WHETHER THE NATURAL LAW IS THE SAME
IN ALL MEN?
We proceed thus to the Fourth Article:
Objection i. It would seem that the natural law
is not the same in all. For it is stated in the Decretals
(Dist. i.) that the natural law is that which is con-
tained in the Law and the Gospel. But this is not
common to all men; because, as it is written (Rom.
x. 1 6), all do not obey the gospel. Therefore the nat-
ural law is not the same in all men.
Ob}. 2. Further, Things which are according to the
law are said to be just, as stated in Ethic, v. But it
is stated in the same book that nothing is so univer-
sally just as not to be subject to change in regard to
some men. Therefore even the natural law is not the
same in all men.
Ob}. 3. Further, as stated above (AA. 2, 3), to the
natural law belongs everything to which a man is
inclined according to his nature. Now different men
are naturally inclined to different things; some to the
desire of pleasures, others to the desire of honours,
and other men to other things. Therefore there is not
one natural law for all.
On the contrary, Isidore says (Etym. v. 4) : The
natural law is common to all nations.
I answer that, As stated above ( AA. 2, 3 ) , to the
OF THE NATURAL LAV 65
natural law belongs those things to which a man is
inclined naturally: and among these it is proper to
man to be inclined to act according to reason. Now
the process of reason is from the common to the
proper, as stated in Pkys. i. The speculative reason,
however, is differently situated in this matter, from
the practical reason. For, since the speculative reason
is busied chiefly with necessary things, which cannot
be otherwise than they are, its proper conclusions,
like the universal principles, contain the truth with-
out fail. The practical reason, on the other hand, is
busied with contingent matters, about which human
actions are concerned: and consequently, although
there is necessity in the general principles, the more
we descend to matters of detail, the more frequently
we encounter defects. Accordingly then in specula-
tive matters truth is the same in all men, both as to
principles and as to conclusions: although the truth
is not known to all as regards the conclusions, but
only as regards the principles which are called common
notions. But in matters of action, truth or practical
rectitude is not the same for all, as to matters of
detail, but only as to the general principles: and
where there is the same rectitude in matters of detail,
it is not equally known to all.
It is therefore evident that, as regards the general
principles whether of speculative or of practical rea-
son, truth or rectitude is the same for all, and is
equally known by all. As to the proper conclusions
of the speculative reason, the truth is the same for
all, but is not equally known to all: thus it is true
66 TREATISE ON LAW
for all that the three angles of a triangle are together
equal to two right angles, although it is not known
to all. But as to the proper conclusions of the prac-
tical reason, neither is the truth or rectitude the same
for all, nor, where it is the same, is it equally known
by all. Thus it is right and true for all to act accord-
ing to reason: and from this principle it follows as
a proper conclusion, that goods entrusted to another
should be restored to their owner. Now this is true
for the majority of cases: but it may happen in a
particular case that it would be injurious, and there-
fore unreasonable, to restore goods held in trust; for
instance if they are claimed for the purpose of fight-
ing against one's country. And this principle will be
found to fail the more, according as we descend
further into detail, e.g., if one were to say that goods
held in trust should be restored with such and such
a guarantee, or in such and such a way; because the
greater the number of conditions added, the greater
the number of ways in which the principle may fail,
so that it be not right to restore or not to restore.
Consequently we must say that the natural law,
as to general principles, is the same for all, both as
to rectitude and as to knowledge. But as to certain
matters of detail, which are conclusions, as it were,
of those general principles, it is the same for all in
the majority of cases, both as to rectitude and as to
knowledge; and yet in some few cases it may fail,
both as to rectitude, by reason of certain obstacles
(just as natures subject to generation and corruption
fail in some few cases on account of some obstacle),
OF THE NATURAL LAW 67
and as to knowledge, since in some the reason is per-
verted by passion, or evil habit, or an evil disposition
of nature; thus formerly, theft, although it is ex-
pressly contrary to the natural law, was not consid-
ered wrong among the Germans, as Julius Caesar
relates (De Bello Gall. vi.).
Reply Obj. i. The meaning of the sentence quoted
is not that whatever is contained in the Law and the
Gospel belongs to the natural law, since they contain
many things that are above nature; but that what-
ever belongs to the natural law is fully contained in
them. Wherefore Gratian, after saying that the nat-
ural law is what is contained in the Law and the
Gospel, adds at once, by way of example, by which
everyone is commanded to do to others as he would
be done by.
Reply Obj. 2. The saying of the Philosopher is to
be understood of things that are naturally just, not
as general principles, but as conclusions drawn from
them, having rectitude in the majority of cases, but
failing in a few.
Reply Obj. 3. As, in man, reason rules and com-
mands the other powers, so all the natural inclina-
tions belonging to the other powers must needs be
directed according to reason. "Wherefore it is univer-
sally right for all men, that all their inclinations
should be directed according to reason.
6$ TREATISE ON LAW
WHETHER THE NATURAL LAW CAN BE CHANGED?
We proceed this to the Fifth Article:
Objection i. It would seem that the natural law
can be changed. Because on Ecclus. xvii. 9, He gave
them instructions, and the law of life, the gloss says:
He wished the law of the letter to be written, in
order to correct the law of nature. But that which
is corrected is changed. Therefore the natural law can
Obj. 2. Further, the slaying of the innocent, adul-
tery, and theft are against the natural law. But we
find these things changed by God: as when God com-
manded Abraham to slay his innocent son (Gen. xxii.
2) ; and when He ordered the Jews to borrow and
purloin the vessels of the Egyptians (Exod. xii. 35);
and when He commanded Osee to take to himself
a wife of fornications (Osee i. 2). Therefore the
natural law can be changed*
Obj. 3. Further, Isidore says (Etym. v. 4) that
the possession of all things in common, and universal
freedom, are matters of natural law. But these things
are seen to be changed by human laws. Therefore it
seems that the natural law is subject to change.
On the contrary, It is said in the Decretals (Dist.
v.): The natural law dates from the creation of the
rational creatiire. It does not vary according to time,
but remains unchangeable.
OF THE NATURAL LAW 69
I answer that, A change in the natural law may be
understood in two ways. First, by way of addition.
In this sense nothing hinders the natural law from
being changed: since many things for the benefit of
human life have been added over and above the nat-
ural law, both by the Divine law and by human
Secondly, a change in the natural law may be un-
derstood by way of subtraction, so that what pre-
viously was according to the natural law, ceases to
be so. In this sense, the natural law is altogether
unchangeable in its first principles: but in its sec-
ondary principles, which, as we have said (A. 4), are
certain detailed proximate conclusions drawn from
the first principles, the natural law is not changed so
that what it prescribes be not right in most cases.
But it may be changed in some particular cases of
rare occurrence, through some special causes hinder-
ing the observance of such precepts, as stated above
Reply Ohj. i. The written law is said to be given
for the correction of the natural law, either because
it supplies what was wanting to the natural law; or
because the natural law was perverted in the hearts
of some men, as to certain matters, so that they es-
teemed those things good which are naturally evil;
which perversion stood in need of correction.
Reply Ob}. 2. All men alike, both guilty and in-
nocent, die the death of nature: which death of na-
ture is inflicted by the power of God on account of
original sin, according to i Kings ii. 6: The Lord
70 TREATISE ON LAW
killeth and maketh alive. Consequently, by the com-
mand of God, death can be inflicted on any man,
guilty or innocent, without any injustice whatever.
In like manner adultery is intercourse with another's
wife; who is allotted to him by the law emanating
from God. Consequently intercourse with any
woman, by the command of God, is neither adultery
nor fornication. The same applies to theft, which
is the taking of another's property. For whatever is
taken by the command of God, to Whom all things
belong, is not taken against the will of its owner,
whereas it is in this that theft consists. Nor is it
only in human things, that whatever is commanded
by God is right; but also in natural things, whatever
is done by God, is, in some way, natural, as stated
in the First Part (Q. CV., A. 6 ad i).
Reply Obj. 3. A thing is said to belong to the
natural law in two ways. First, because nature in-
clines thereto: e.g., that one should not do harm to
another. Secondly, because nature did not bring in
the contrary: thus we might say that for man to be
naked is of the natural law, because nature did not
give him clothes, but art invented them. In this sense,
the possession of all things in common and universal
freedom are said to be of the natural law, because, to
wit, the distinction of possessions and slavery were not
brought in by nature, but devised by human reason
for the benefit of human life. Accordingly the law of
nature was not changed in this respect, except by
OF THE NATURAL LAW 71
WHETHER THE LAW OF NATURE CAN BE
ABOLISHED FROM THE HEART OF MAN?
We proceed thus to the Sixth Article:
Objection i. It would seem that the natural law
can be abolished from the heart of man. Because on
Rom. ii. 14, When the Gentiles who have not the
law, etc., a gloss says that the law of righteousness)
which sin had blotted out, is graven on the heart of
man when he is restored by grace. But the law of
righteousness is the law of nature. Therefore the law
of nature can be blotted out.
Obj. 2. Further, the law of grace is more effica-
cious than the law of nature. But the law of grace
is blotted out by sin. Much more therefore can the
law of nature be blotted out.
Obj. 3. Further, that which is established by law
is made just. But many things are enacted by men,
which are contrary to the law of nature. Therefore
the law of nature can be abolished from the heart of
On the contrary, Augustine says (Conf. ii.) : Thy
law is written in the hearts of men, which iniquity
itself effaces not. But the law which is written in
men's hearts is the natural law. Therefore the nat-
ural law cannot be blotted out.
I answer that, As stated above (AA. 4, 5), there
72 TREATISE ON LAW
belong to the natural law, first, certain most general
precepts, that are known to all; and secondly, certain
secondary and more detailed precepts, which are, as
it were, conclusions following closely from first prin-
ciples. As to those general principles, the natural law,
in the abstract, can nowise be blotted out from men's
hearts. But it is blotted out in the case of a particular
action, in so far as reason is hindered from applying
the general principle to a particular point of practice,
on account of concupiscence or some other passion,
as stated above (Q. LXXVIL, A. 2). But as to the
other, i.e., the secondary precepts, the natural law
can be blotted out from the human heart, either by
evil persuasions, just as in speculative matters errors
occur in respect of necessary conclusions; or by vi-
cious customs and corrupt habits, as among some
men, theft, and even unnatural vices, as the Apostle
states (Rom. i.), were not esteemed sinful.
Reply Obj. i. Sin blots out the law of nature in
particular cases, not universally, except perchance in
regard to the secondary precepts of the natural law,
in the way stated above.
Reply Ob}. 2. Although grace is more efficacious
than nature, yet nature is more essential to man, and
therefore more enduring.
Reply Ob]. 3. This argument is true of the second-
ary precepts of the natural law, against which some
legislators have framed certain enactments which are
OF HUMAN LAW 73
OF HUMAN LAW
(In Four Articles)
must now consider human law; and (i) this law
considered in itself; (2) its power; (3) its mutabil-
ity. Under the first head there are four points of
inquiry: (i) Its utility. (2) Its origin (3) Its qual-
ity. (4) Its division.
WHETHER IT WAS USEFUL FOR LAWS TO BE
FRAMED BY MEN?
We proceed thus to the First Article:
Objection i. It would seem that it was not useful
for laws to be framed by men. Because the purpose
of every law is that man be made good thereby, as
stated above (Q. XCIL, A. i). But men are more to
be induced to be good willingly by means of admoni-
tions, than against their will, by means of laws.
Therefore there was no need to frame laws.
Obj. 2. Further, as the Philosopher says (Ethic.
v. 4), men have recourse to a judge as to animate
74 TREATISE ON LAW
justice. But animate justice is better than inanimate
justice, which is contained in laws. Therefore it
would have been better for the execution of justice
to be entrusted to the decision of judges, than to
frame laws in addition.
Obj. 3. Further, every law is framed for the direc-
tion of human actions, as is evident from what has
been stated above (Q. XC., AA. i, 2). But since
human actions are about singulars, which are infinite
in number, matters pertaining to the direction of
human actions cannot be taken into sufficient con-
sideration except by a wise man, who looks into each
one of them. Therefore it would have been better for
human acts to be directed by the judgment of wise
men, than by the framing of laws. Therefore there
was no need of human laws.
On the contrary, Isidore says (Etym. v, 20) : Laws
were made that in fear thereof human audacity might
be held in cheeky that innocence might be safeguarded
in the midst of wickedness, and that the dread of
punishment might prevent the wicked from doing
harm. But these things are most necessary to mankind.
Therefore it was necessary that human laws should
I answer that, As stated above (Q. LXIIL, A. i;
Q. XCIV., A. 3), man has a natural aptitude for
virtue; but the perfection of virtue must be acquired
by man by means of some kind of training. Thus we
observe that man is helped by industry in his neces-
sities, for instance, in food and clothing. Certain
OF HUMAN LAW 75
beginnings of these he has from nature, viz., his rea-
son and his hands; but he has not the full compli-
ment, as other animals have, to whom nature has
given sufficiency of clothing and food. Now it is
difficult to see how man could suffice for himself in
the matter of this training: since the perfection of
virtue consists chiefly in withdrawing man from un-
due pleasures, to which above all man is inclined,
and especially the young, who are more capable of
being trained. Consequently a man needs to receive
this training from another, whereby to arrive at the
perfection of virtue. And as to those young people
who are inclined to acts of virtue, by their good
natural disposition, or by custom, or rather by the
gift of God, paternal training suffices, which is by
admonitions. But since some are found to be depraved,
and prone to vice, and not easily amenable to words,
it was necessary for such to be restrained from evil
by force and fear, in order that, at least, they might
desist from evildoing, and leave others in peace, and
that they themselves, by being habituated in this
way, might be brought to do willingly what hitherto
they did from fear, and thus become virtuous. Now
this kind of training, which compels through fear
of punishment, is the discipline of laws. Therefore,
in order that man might have peace and virtue, it
was necessary for laws to be framed: for, as the
Philosopher says (Polit. i. 2), as man is the most
noble of animals, if he be perfect in virtue, so is he
the lowest of all, if he be severed from law and right-
7 6 TREATISE ON LAW
cousness; because man can use his reason to devise
means of satisfying his lusts and evil passions, which
other animals are unable to do.
Reply Ob}, i. Men who are well disposed are led
willingly to virtue by being admonished better than
by coercion: but men who are evilly disposed are not
led to virtue unless they are compelled.
Reply Ob}. 2. As the Philosopher says (Rhet. i. i ) ,
// is better that all things be regulated by law, than
left to be decided by judges: and this for three rea-
sons. First, because it is easier to find a few wise men
competent to frame right laws, than to find the
many who would be necessary to judge aright of
each single case. Secondly, because those who make
laws consider long beforehand what laws to make;
whereas judgment on each single case has to be pro-
nounced as soon as it arises: and it is easier for man
to see what is right, by taking many instances into
consideration, than by considering one solitary fact.
Thirdly, because lawgivers judge in the abstract
and of future events; whereas those who sit in judg-
ment judge of things present, towards which they
are affected by love, hatred, or some kind of cupidity;
wherefore their judgment is perverted.
Since then the animated justice of the judge is not
found in every man, and singe it can be deflected, it
was necessary, whenever possible, for the law to de-
termine how to judge, and for very few matters to be
left to the decision of men.
Reply Ob}. 3. Certain individual facts which can-
not be covered by the law have necessarily to be
OF HUMAN LAW 77
committed to judges, as the Philosopher says in the
same passage: for instance, concerning something that
has happened or not happened) and the like.
WHETHER EVERY HUMAN LAW IS DERIVED FROM
THE NATURAL LAW?
We proceed tJms to the Second Article:
Objection i. It would seem that not every human
law is derived from the natural law. For the Philos-
opher says (Ethic, v. 7) that the legal just is that
which originally was a matter of indifference. But
those things which arise from the natural law are not
matters of indifference. Therefore the enactments o
human laws are not all derived from the natural law.
Obj. 2. Further, positive law is contrasted with
natural law, as stated by Isidore (Etym. v. 4) and
the Philosopher (Ethic, v,, loc. cit.). But those things
which flow as conclusions from the general princi-
ples of the natural law belong to the natural law, as
stated above (Q. XCIV., A. 4). Therefore that
which is established by human law does not belong
to the natural law.
Obj. 3. Further, the law of nature is the same for
all; since the Philosopher says (Ethic, v. 7) that the
natural just is that which is equally -valid everywhere.
If therefore human laws were derived from the nat-
78 TREATISE ON LAW
ural laws, it would follow that they too are the same
for all: which is clearly false.
Ob}. 4. Further, it is possible to give a reason for
things which are derived from the natural law. But
it h not possible to give the reason for all the legal
enactments of the lawgivers, as the jurist says.*
Therefore not all human laws are derived from the
On the contrary, Tully says (Rhetor, ii.) : Things
which emanated from natiire and were approved by
custom, were sanctioned by fear and reverence for
I answer that, As Augustine says (De Lib. Arb.
i. 5 ) , that which is not just seems to be no law at all:
wherefore the force of a law depends on the extent
of its justice. Now in human affairs a thing is said
to be just, from being right, according to the rule of
reason. But the first rule of reason is the law of na-
ture, as is clear from what has been stated above
(Q. XCL, A. 2 ad 2). Consequently every human
law has just so much of the nature of law, as it is
derived from the law of nature. But if in any point
it deflects from the law of nature, it is no longer a
law but a perversion of law.
But it must be noted that something may be de-
rived from the natural law in two ways: first, as a
conclusion from premisses, secondly, by way of de-
termination of certain generalities. The first way is
like to that by which, in sciences, demonstrated con-
clusions are drawn from the principles: while the
* Pandect. Jmtin, lib. i. ff., tit. iii., art. v., De Leg. et Senat.
OF HUMAN LAW 79
second mode is likened to that whereby, in the arts,
general forms are particularized as to details: thus the
craftsman needs to determine the general form of a
house to some particular shape. Some things are there-
fore derived from the general principles of the nat-
ural law, by way of conclusions; e.g., that one must
not kill may be derived as a conclusion from the
principle that one should do harm to no man:
while some are derived therefrom by way of deter-
mination; e.g., the law of nature has it that the evil-
doer should be punished; but that he be punished in
this or that way, is a determination of the law of
Accordingly both modes of derivation are found
in the human law. But those things which are de-
rived in the first way, are contained in human law
not as emanating therefrom exclusively, but have
some force from the natural law also. But those
things which are derived in the second way, have no
other force than that of human law.
Reply Obj. i. The Philosopher is speaking of those
enactments which are by way of determination or
specification of the precepts of the natural law.
Reply Obj. 2. This argument avails for those
things that are derived from the natural law, by
way of conclusions.
Reply Obj. 3. The general principles of the natural
law cannot be applied to all men in the same way on
account of the great variety of human affairs: and
hence arises the diversity of positive laws among
So TREATISE ON LAW
Reply Obj. 4. These words of the Jurist are to be
understood as referring to decisions of rulers in de-
termining particular points of the natural law: on
which determinations the judgment of expert and
prudent men is based as on its principles; in so far,
to wit, as they see at once what is the best thing to
Hence the Philosopher says (Ethic, vi. n) that
in such matters, we ought to pay as much attention
to the undemonstrated sayings and opinions of per-
sons who surpass us in experience, age and prudence,
as to their demonstrations.
WHETHER ISIDORE'S DESCRIPTION OF THE QUALITY
OF POSITIVE LAW IS APPROPRIATE?
We proceed thus to the Third Article:
Objection i. It would seem that Isidore's descrip-
tion of the quality of positive law is not appropriate,
when he says (Etym. v. 21) : Law shall be virtuous,
just, possible to nature, according to the custom of
the country, suitable to place and time, necessary,
useful; clearly expressed, lest by its obscurity it lead
to misunderstanding; framed for no private benefit,
but for the common good. Because he had previously
expressed the quality of law in three conditions, say-
ing that law is anything founded on reason, provided
that it foster religion, be helpful to discipline, and
OF HUMAN LAW 8 1
further the common weal. Therefore it was needless
to add any further conditions to these.
Obj. z. Further, Justice is included in honesty, as
Tully says (De Offic. vii.). Therefore after saying
honest it was superfluous to add just.
Ob}. 3. Further, written law is condivided with
custom, according to Isidore (Etym, ii. 10). There-
fore it should not be stated in the definition of law
that it is according to the custom of the country.
Obj. 4. Further, a thing may be necessary in two
ways. It may be necessary simply, because it cannot
be otherwise: and that which is necessary in this way,
is not subject to human judgment, wherefore human
law is not concerned with necessity of this kind.
Again a thing may be necessary for an end: and this
necessity is the same as usefulness. Therefore it is
superfluous to say both necessary and useful.
On the contrary stands the authority of Isidore.
7 answer that, Whenever a thing is for an end, its
form must be determined proportionately to that
end; as the form of a saw is such as to be suitable
for cutting (Phys. ii., text. 88). Again, everything
that is ruled and measured must have a form pro-
portionate to its rule and measure. Now both these
conditions are verified of human law: since it is both
something ordained to an end; and is a rule or meas-
ure ruled or measured by a higher measure. And this
higher measure is twofold, viz., the Divine law and
the natural law, as explained above (A. 2; Q. XCIIL,
A. 3 ) . Now the end of human law is to be useful to
man, as the Jurist states.* 'WTierefore Isidore in de-
* Pandect. Just. lib. xxv. ?., tit. iii., De Leg. et Senat.
82 TREATISE ON LAW
termining the nature of law, lays down, at first, three
conditions; viz., that it foster religion, inasmuch as
it is proportionate to the Divine law; that it be help-
ful to discipline, inasmuch as it is proportionate to
the natural law; and that it further the common
weal, inasmuch as it is proportionate to the utility
All the other conditions mentioned by him are
reduced to these three. For it is called virtuous be-
cause it fosters religion. And when he goes on to say
that it should be just, possible to nature, according
to the customs of the country, adapted to place and
time, he implies that it should be helpful to disci-
pline. For human discipline depends first on the order
of reason, to which he refers by saying just:
secondly, it depends on the ability of the agent; be-
cause discipline should be adapted to each one ac-
cording to his ability, taking also into account the
ability of nature (for the same burdens should be not
laid on children as on adults) ; and should be accord-
ing to human customs; since man cannot live alone
in society, paying no heed to others: thirdly, it
depends on certain circumstances, in respect of which
he says, adapted to place and time. The remaining
words, necessary, useful, etc., mean that law should
further the common weal: so that necessity refers to
the removal of evils; usefulness to the attainment of
good; clearness of expression, to the need of prevent-
ing any harm ensuing from the law itself. And
since, as stated above (Q. XC, A. 2), law is ordained
OF HUMAN LAW 83
to the common good, this is expressed in the last part
of the description.
This suffices for the Replies to the Objections.
WHETHER ISIDORE'S DIVISION OF HUMAN LAWS
We proceed tlms to the Fourth Article:
Objection i. It would seem that Isidore wrongly
divided human statutes or human law (Etym. v. 4
seqq.). For under this law he includes the law of na-
tions, so called, because, as he says, nearly all nations use
it. But as he says, natural law is that -which is common
to all nations. Therefore the law of nations is not con-
tained under positive human law, but rather under
Ob}. 2. Further, those laws which have the same
force, seem to differ not formally but only materially.
But statutes, decrees of the commonalty, senatorial
decrees, and the like which he mentions (ibid., 9),
all have the same force. Therefore they do not differ,
except materially. But art takes no notice of such a
distinction: since it may go on to infinity. Therefore
this division of human laws is not appropriate.
Ob}. 3. Further, just as, in the state, there are
princes, priests and soldiers, so are there other human
offices. Therefore it seems that, as this division in-
cludes military law, and public law, referring to
84 TREATISE ON LAW
priests and magistrates; so also it should include other
laws pertaining to other offices of the state.
Obj. 4. Further, those things that are accidental
should be passed over. But it is accidental to law that
it be framed by this or that man. Therefore it is un-
reasonable to divide laws according to the names of
lawgivers, so that one be called the Cornelian law,
another the Falcidian law, etc,
On the contrary, The authority of Isidore (Obj.
7 answer that, A thing can of itself be divided in
respect of something contained in the notion of that
thing. Thus a soul either rational or irrational is con-
tained in the notion of animal: and therefore animal
is divided properly and of itself in respect of its being
rational or irrational; but not in the point of its be-
ing white or black, which are entirely beside the no-
tion of animal. Now, in the notion of human law,
many things are contained, in respect of any of which
human law can be divided properly and of itself. For
in the first place it belongs to the notion of human
law, to be derived from the law of nature, as ex-
plained above (A. 2). In this respect positive law is
divided into the law of nations and civil law, accord-
ing to the two ways in which something may be de-
rived from the law of nature, as stated above (A. 2).
Because, to the law of nations belong those things
which are derived from the law of nature, as conclu-
sions from premisses, e.g., just buyings and sellings,
and the like, without which men cannot live together,
which is a point of the law of nature, since man is by
OF HUMAN LAW 85
nature a social animal, as is proved in Polit. i. 2. But
those things which are derived from the law of nature
by way of particular determination, belong to the
civil law, according as each state decides on what is
best for itself.
Secondly, it belongs to the notion of human law,
to be ordained to the common good of the state. In
this respect human law may be divided according to
the different kinds of men who work in a special way
for the common good: e.g., priests, by praying to
God for the people; princes, by governing the people;
soldiers, by fighting for the safety of the people.
"Wherefore certain special kinds of law are adapted to
Thirdly, it belongs to the notion of human law, to
be framed by that one who governs the community
of the state, as shown above (Q. XC., A. 3 ) . In this
respect, there are various human laws according to
the various forms of government. Of these, according
to the Philosopher (Polit. iii. 10) one is monarchy, i.e.,
when the state is governed by one; and then we have
Royal Ordinances. Another form is aristocracy, i.e.,
government by the best men or men of highest rank;
and then we have the Authoritative legal opinions
(Responsa Prudentum) and Decrees of the Senate
(Senatus consult a). Another form is oligarchy, i.e.,
government by a few rich and powerful men; and
then we have Praetorian, also called Honorary, law.
Another form of government is that of the people,
which is called democracy, and there we have Decrees
of the commonalty (Plebiscita) . There is also tyran-
86 TREATISE ON LAW
nical government, which is altogether corrupt, which,
therefore, has no corresponding law. Finally, there is
a form of government made up of all these, and which
is the best: and in this respect we have law sane-
tioned by the Lords and Commons, as stated by
Isidore (/or. cit.).
Fourthly, it belongs to the notion of human law
to direct human actions. In this respect, according to
the various matters of which the law treats, there are
various kinds of laws, which are sometimes named
after their authors: thus we have the Lex Julia about
adultery, the Lex Cornelia concerning assasins, and
so on, differentiated in this way, not on account of
the authors, but on account of the matters to which
Reply Obj. i. The law of nations is indeed, in some
way, natural to man, in so far as he is a reasonable
being, because it is derived from the natural law by
way of a conclusion that is not very remote from its
premisses. Wherefore men easily agreed thereto.
Nevertheless it is distinct from the natural law, es-
pecially from that natural law which is common to
The Replies to the other Objections are evident
from what has been said.
OF THE POWER OF HUMAN LAW 87
OF THE POWER OF HUMAN LAW
(In Six Articles)
must now consider the power of human law.
Under this head there are six points of inquiry: (i)
Whether human law should be framed for the com-
munity? (2) Whether human law should repress all
vices? (3) Whether human law is competent to direct
all acts of virtue? (4) Whether it binds man in
conscience? (j) Whether all men are subject to hu-
man law? (6) Whether those who are under the law
may act beside the letter of the law?
WHETHER HUMAN LAW SHOULD BE FRAMED FOR
THE COMMUNITY RATHER THAN FOR THE
We proceed thus to the First Article:
Objection i. It would seem that human law should
be framed not for the community, but rather for the
individual. For the Philosopher says (Ethic, v. 7) that
the legal just . . . includes all particular acts of legis-
lation . . . and all those matters which are the subject
of decrees, which are also individual matters, since
88 TREATISE ON LAW
decrees are framed about individual actions. There-
fore law is framed not only for the community, but
also for the individual.
Ob). 2. Further, law is the director of human acts,
as stated above (Q. XC., A A. i, 2). But human acts
are about individual matters. Therefore human laws
should be framed, not for the community, but rather
for the individual.
Ob). 3. Further, law is a rule and measure of hu-
man acts, as stated above (Q. XC., AA. i, 2). But
a measure should be most certain, as stated in Metaph.
x. Since therefore in human acts no general proposi-
tion can be so certain as not to fail in some individual
cases, it seems that laws should be framed not in
general but for individual cases.
On the contrary, The jurist says ("Pandect, ]^lstin,
lib. i., tit. iii., art. ii., De le gibus, etc.) that laws
should be made to suit the majority of instances; and
they are not framed according to what may possibly
happen in an individual case.
I answer that, Whatever is for an end should be
proportionate to that end. Now the end of law is the
common good; because, as Isidore says (Etym. v. 21)
that law should be framed, not for any private bene-
fit, but for the common good of all the citizens.
Hence human laws should be proportionate to the
common good. Now the common good comprises
many things. Wherefore laws should take account of
many things, as to persons, as to matters, and as to
times. Because the community of the state is com-
posed of many persons; and its good is procured by
OF THE POWER OF HUMAN LAW 89
many actions; nor is it established to endure for only
a short time, but to last for all time by the citizens
succeeding one another, as Augustine says (De Civ.
Dei ii. 21; xxii. 6).
Reply Ob}, i. The Philosopher (Ettic. v.j) divides
the legal just, i.e., positive law, into three parts. For
some things are laid down simply in a general way:
and these are the general laws. Of these he says that the
legal is that which originally was a matter of indiffer-
ence, but ^vhich, ivhen enacted, is so no longer: as the
fixing of the ransom of a captive. Some things affect
the community in one respect, and individuals in an-
other. These are called privileges, i.e., private laws, as
it were, because they regard private persons, although
their power extends to many matters; and in regard
to these, he adds, and further, all particular acts of
legislation. Other matters are legal, not through be-
ing laws, but through being applications of general
laws to particular cases: such are decrees which have
the force of law; and in regard to these, he adds all
matters subject to decrees.
Reply Ob}. 2. A principle of direction should be
applicable to many; wherefore (Metaph. x., text. 4)
the Philosopher says that all things belonging to one
genus, are measured by one, which is the principle in
that genus. For if there were as many rules or meas-
ures as there are things measured or ruled, they would
cease to be of use, since their use consists in being
applicable to many things. Hence law would be of no
use, if it did not extend further than to one single
act. Because the decrees of prudent men are made for
90 TREATISE ON LAW
the purpose of directing individual actions; whereas
law is a general precept, as stated above (Q. XCIL,
A. 2, Obj. 2).
Reply Obj. 3. We must not seek the same degree
of certainty in all things (Ethic, i. 3). Consequently
in contingent matters, such as natural and human
things, it is enough for a thing to be certain, as being
true in the greater number of instances, though at
times and less frequently it fail.
WHETHER IT BELONGS TO HUMAN LAW TO
REPRESS ALL VICES?
We proceed thus to the Second Article:
Objection i. It would seem that it belongs to hu-
man law to repress all vices. For Isidore says (Etym.
v. 20) that laws were made in order that, in fear
thereof) man's audacity might be held in check. But
it would not be held in check sufficiently, unless all
evils were repressed by law. Therefore human law
should repress all evils.
Ob]. 2. Further, the intention of the lawgiver is to
make the citizens virtuous. But a man cannot be
virtuous unless he forbear from all kinds of vice.
Therefore it belongs to human law to repress all vices.
Obj. 3. Further, human law is derived from the
natural law, as stated above (Q. XCV., A. 2). But
OF THE POWER OF HUMAN LAV 91
all vices are contrary to the law of nature. Therefore
human law should repress all vices.
On the contrary, We read in De Lib. Arb. i. 5 : //
seems to me that the law which is -written for the
governing of the people rightly permits these things,
and that Divine providence punishes them. But Divine
providence punishes nothing but vices. Therefore hu-
man law rightly allows some vices, by not repressing
I answer that, As stated above (Q. XC., AA. 1,2),
law is framed as a rule or measure of human acts.
Now a measure should be homogeneous with that
which it measures, as stated in Metaph. x., text. 3, 4,
since different things are measured by different meas-
ures. Wherefore laws imposed on men should also be
in keeping with their condition, for, as Isidore says
(Etym. v. 21 ), law should be possible both according
to nature t and according to the customs of the conn-
try. Now possibility or faculty of action is due to an
interior habit or disposition: since the same thing is
not possible to one who has not a virtuous habit, as is
possible to one who has. Thus the same is not possible
to a child as to a full-grown man: for which reason
the law for children is not the same as for adults,
since many things are permitted to children, which in
an adult are punished by law or at any rate are
open to blame. In like manner many things are per-
missible to men not perfect in virtue, which would be
intolerable in a virtuous man.
Now human law is framed for a number of human
beings, the majority of whom are not perfect in vir-
92 TREATISE ON LAW
tue. Wherefore human laws do not forbid all vices,
from which the virtuous abstain, but only the more
grievous vices, from which it is possible for the ma-
jority to abstain; and chiefly those that are to the hurt
of others, without the prohibition of which human
society could not be maintained: thus human law
prohibits murder, theft and suchlike.
Reply Ob}, i. Audacity seems to refer to the as-
sailing of others. Consequently it belongs to those
sins chiefly whereby one's neighbour is injured: and
these sins are forbidden by human law, as stated.
Reply Ob). 2. The purpose of human law is to lead
men to virtue, not suddenly, but gradually. Where-
fore it does not lay upon the multitude of imperfect
men the burdens of those who are already virtuous,
viz., that they should abstain from all evil. Otherwise
these imperfect ones, being unable to bear such pre-
cepts, would break out into yet greater evils: thus it
is written (Prov. xxx. 33) : He that violently bloweth
bis nose y bringeth out bloody and (Matth. ix. 17)
that if new wine> i.e., precepts of a perfect life, is
put into old bottles, i.e., into imperfect men, the
bottles break, and the wine runneth out, i.e., the
precepts are despised, and those men, from contempt,
break out into evils worse still.
Reply Ob]. 3. The natural law is a participation
in us of the eternal law: while human law falls short
of the eternal law. Now Augustine says (De Lib.
Arb. i. 5 ) : The law which is framed for the govern-
went of states, allows and leaves unpunished many
things that are punished by Divine providence. Nor,
OF THE POWER OF HUMAN LAW 93
if this law does not attempt to do everything, is this
a reason why it should be blamed for what it does.
Wherefore, too, human law does not prohibit every-
thing that is forbidden by the natural law.
WHETHER HUMAN LAW PRESCRIBES ACTS OF ALL
We proceed thus to the Tlnrd Article:
Objection i. It would seem that human law does
not prescribe acts of all the virtues. For vicious acts
are contrary to acts of virtue. But human law does
not prohibit all vices, as stated above (A. 2). There-
fore neither does it prescribe all acts of virtue.
Ob}. 2. Further, a virtuous act proceeds from a
virtue. But virtue is the end of law; so that whatever
is from a virtue, cannot come under a precept of law.
Therefore human law does not prescribe all acts of
Ob}. 3. Further, law is ordained to the common
good, as stated above (Q. XC., A. 2). But some acts
of virtue are ordained, not to the common good, but
to private good. Therefore the law does not prescribe
all acts of virtue.
On the contrary, The Philosopher says (Ethic, v.
i) that the law prescribes the performance of the
acts of a brave man, . . . and the acts of the temperate
man, . . . and the acts of the meek man: and in like
94 TREATISE ON LAW
manner as regards the other virtues and vices, pre-
scribing the former, forbidding the latter.
I answer that, The species of virtues are distin-
guished by their objects, as explained above (Q. LIV.,
A. 2; Q. LX., A. i; Q. LXIL, A. 2). Now all the
objects of virtues can be referred either to the private
good of an individual, or to the common good of the
multitude: thus matters of fortitude may be achieved
either for the safety of the state, or for upholding
the rights of a friend, and in like manner with the
other virtues. But law, as stated above (Q. XC., A.
2) is ordained to the common good. Wherefore there
is no virtue whose acts cannot be prescribed by the
law. Nevertheless human law does not prescribe con-
cerning all the acts of every virtue: but only in re-
gard to those that are ordainable to the common good,
either immediately, as when certain things are done
directly for the common good, or mediately, as when
a lawgiver prescribes certain things pertaining to
good order, whereby the citizens are directed in the
upholding of the common good of justice and peace.
Reply Obj. i. Human law does not forbid all
vicious acts, by the obligation of a precept, as neither
does it prescribe all acts of virtue. But it forbids certain
acts of each vice, just as it prescribes some acts of each
Reply Obj. 2. An act is said to be an act of virtue
in two ways. First, from the fact that a man does
something virtuous; thus the act of justice is to do
what is right, and an act of fortitude is to do brave
things: and in this way law prescribes certain acts of
OF THE POWER OF HUMAN LAW 9^
virtue. Secondly an act of virtue is when a man
does a virtuous thing in a way in which a virtuous man
does it. Such an act always proceeds from virtue: and
it does not come under a precept of law, but is the
end at which every lawgiver aims.
Reply Ob]. 3. There is no virtue whose act is not
ordainable to the common good, as stated above,
either mediately or immediately.
WHETHER HUMAN LAW BINDS A MAN IN
We proceed thus to the fourth Article:
Objection i. It would seem that human law does
not bind a man in conscience. For an inferior power
has no jurisdiction in a court of higher power. But
the power of a man, which frames human law, is
beneath the Divine power. Therefore human law can-
not impose its precept in a Divine court, such as is
the court of conscience.
Ob}. 2. Further, the judgment of conscience de-
pends chiefly on the commandments of God. But
sometimes God's commandments are made void by hu-
man laws, according to Matth. xv. 6: You have made
void the commandment of God for your tradition.
Therefore human law does not bind a man in
Ob}. 3. Further, human laws often bring loss of
9 6 TREATISE ON LAW
character and injury on man, according to Isa. x. i
et seq.: Woe to them that make wicked laws, and
when they write, write injustice; to oppress the poor
in judgment, and do violence to the cause of the
humble of My people. But it is lawful for anyone to
avoid oppression and violence. Therefore human laws
do not bind man in conscience.
On the contrary, It is written (i Pet. ii. 19) : This
is thanksworthy, if for conscience . . . a man endure
sorrows, suffering wrongfully.
I answer that, Laws framed by man are either just
or unjust. If they be just, they have the power of
binding in conscience, from the eternal law whence
they are derived, according to Prov. viii. 15: By Me
kings reign, and lawgivers decree just things. Now
laws are said to be just, both from the end, when,
to wit, they are ordained to the common good, and
from their author, that is to say, when the law that is
made does not exceed the power of the lawgiver,
and from their form, when, to wit, burdens are laid
on the subjects, according to an equality of propor-
tion and with a view to the common good. For, since
one man is a part of the community, each man, in all
that he is and has, belongs to the community; just as
a part, in all that it is, belongs to the whole; wherefore
nature inflicts a loss on the part, in order to save the
whole: so that on this account, such laws as these,
which impose proportionate burdens, are just and
binding in conscience, and are legal laws.
On the other hand laws may be unjust in two ways:
first, by being contrary to human good, through
OF THE POWER OF HUMAN LAW 97
being opposed to the things mentioned above: either
in respect of the end, as when an authority imposes
on his subjects burdensome laws, conducive, not to
the common good, but rather to his own cupidity or
vainglory;- or in respect of the author, as when a
man makes a law that goes beyond the power com-
mitted to him; or in respect of the form, as when
burdens are imposed unequally on the community, al-
though with a view to the common good. The like
are acts of violence rather than laws; because as
Augustine says (De Lib. Arb. i. 5), a law that is not
just) seems to be no law at all. Wherefore such laws
do not bind in conscience, except perhaps in order to
avoid scandal or disturbance, for which cause a man
should even yield his right, according to Matth. v. 40,
41: If a -man . . . take away thy coat, let go thy cloak
also unto him; and whosoever will force thee one mile,
go with him other two.
Secondly, laws may be unjust through being op-
posed to the Divine good: such are the laws of tyrants
inducing to idolatry, or to anything else contrary to
the Divine law: and laws of this kind must nowise
be observed, because, as stated in Acts v. 29, we
ought to obey God rather than men.
Reply Obj. i. As the Apostle says (Rom. xiii. i,
2), all human power is from God . . . therefore he
that resisteth the power, in matters that are within its
scope, resisteth the ordinance of God; so that he be-
comes guilty according to his conscience.
Reply Obj. 2. This argument is true of laws that
are contrary to the commandments of God, which is
98 TREATISE ON LAW
beyond the scope of (human) power. Wherefore in
such matters human law should not be obeyed.
Reply Obj. 3. This argument is true of a law that
inflicts unjust hurt on its subjects. The power that
man holds from God does not extend to this: where-
fore neither in such matters is man bound to obey the
law, provided he avoid giving scandal or inflicting a
more grievous hurt.
WHETHER ALL ARE SUBJECT TO THE LAW?
We proceed thus to the Fifth Article:
Objection i. It would seem that not all are subject
to the law. For those alone are subject to a law for
whom a law is made. But the Apostle says (i Tim.
i. 9 ) : The law is not made for the just man. There-
fore the just are not subject to the law.
Ob}. 2. Further, Pope Urban says:* He that is
guided by a private law need not for any reason be
bound by the public law. Now all spiritual men are
led by the private law of the Holy Ghost, for they
are the sons of God, of whom it is said (Rom. viii.
14) : Whosoever are led by the Spirit of God, they are
the sons of God. Therefore not all men are subject to
* Decret. caus. xix., qu. 2.
OF THE POWER OF HUMAN LAW 99
Obj. 3. Further, the jurist says* that the sovereign
is exempt from the laws. But he that is exempt from
the law is not bound thereby. Therefore not all are
subject to the law.
On the contrary) The Apostle says (Rom. xiii. i) :
Let every soul be subject to the higher powers. But
subjection to a power seems to imply subjection to the
laws framed by that power. Therefore all men should
be subject to human law.
Z answer that, As stated above (Q. XC, AA. i,
2; A. 3 ad 2), the notion of law contains two things;
first, that it is a rule of human acts; secondly, that it
has coercive power. Wherefore a man may be subject to
law in two ways. First, as the regulated is subject
to the regulator: and, in this way, whoever is subject
to a power, is subject to the law framed by that
power. But it may happen in two ways that one is
not subject to a power. In one way, by being altogether
free from its authority: hence the subjects of one
city or kingdom are not bound by the laws of the
sovereign of another city or kingdom, since they are
not subject to his authority. In another way, by be-
ing under a yet higher law; thus the subject of a
proconsul should be ruled by his command, but not
in those matters in which the subject receives his
orders from the emperor: for in these matters, he is
not bound by the mandate of the lower authority,
since he is directed by that of a higher. In this way,
one who is simply subject to a law, may not be sub-
* Pandect. Justin, i. ff., tit. 3, De Leg. et Senat.
100 TREATISE ON LAW
ject thereto in certain matters, in respect of which he
is ruled by a higher law.
Secondly, a man is said to be subject to a law as
the coerced is subject to the coercer. In this way the
virtuous and righteous are not subject to the law, but
only the wicked. Because coercion and violence are
contrary to the will: but the will of the good is in
harmony with the law, whereas the will of the wicked
is discordant from it. Wherefore in this sense the
good are not subject to the law, but only the wicked.
Reply Obj. i. This argument is true of subjection
by way of coercion: for, in this way, the law is not
made for the just men: because they are a law to
themselves, since they shew the work of the law
written in their hearts, as the Apostle says (Rom. ii.
14, 15). Consequently the law does not enforce itself
upon them as it does on the wicked.
Reply Obj. 2. The law of the Holy Ghost is above
all law framed by man: and therefore spiritual men,
in so far as they are led by the law of the Holy
Ghost, are not subject to the law in those matters
that are inconsistent with the guidance of the Holy
Ghost. Nevertheless the very fact that spiritual men
are subject to law, is due to the leading of the Holy
Ghost, according to i Pet. ii. 13: Be ye subject . . .
to every human creature for God's sake.
Reply Obj. 3. The sovereign is said to be exempt
from the law, as to its coercive power; since, properly
speaking, no man is coerced by himself, and law has
no coercive power save from the authority of the
sovereign. Thus then is the sovereign said to be ex-
OF THE POWER OF HUMAN LAW IOI
empt from the law, because none is competent to pass
sentence on him, if he acts against the law. "Where-
fore on Ps. L. 6: To Thee only have I sinned, a gloss
says that there is no man who can judge the deeds of
a king. But as to the directive force of law, the
sovereign is subject to the law by his own will, ac-
cording to the statement (Extra, De Cons tit. cap.
Cum omnes) that whatever law a man makes for an-
other, he should keep himself. And a wise authority*
says: 'Obey the law that thou makes t thyself. 3 More-
over the Lord reproaches those who say and do not;
and who bind heavy burdens and lay them on men's
shoidders, but with a finger of their own they will
not move them (Matth. xxiii. 3, 4). Hence, in the
judgment of God, the sovereign is not exempt from
the law, as to its directive force; but he should fulfil
it of his own free-will and not of constraint.
Again the sovereign is above the law, in so far as,
when it is expedient, he can change the law, and dis-
pense in it according to time and place.
WHETHER HE WHO IS UNDER A LAW MAY ACT
BESIDE THE LETTER OF THE LAW?
We proceed thus to the Sixth Article:
Objection i. It seems that he who is subject to a
law may not act beside the letter of the law. For
* Dionysius Cato, Dist. de Moribus.
102 TREATISE ON LAW
Augustine says (De Vera Relig. xxxi) : Although
men judge about temporal laws when they make
them, yet when once they are made they imist pass
judgment not on them, but according to them. But if
anyone disregard the letter of the law, saying that he
observes the intention of the lawgiver, he seems to
pass judgment on the law. Therefore it is not right
for one who is under a law to disregard the letter of
the law, in order to observe the intention of the law-
Obj. 2. Further, he alone is competent to interpret
the law who can make the law. But those who are
subject to the law cannot make the law. Therefore
they have no right to interpret the intention of the
lawgiver, but should always act according to the
letter of the law.
Obj. 3 . Further, every wise man knows how to ex-
plain his intention by words. But those who framed the
laws should be reckoned wise: for Wisdom says (Prov.
viii. 15): By Me kings reign, and lawgivers decree just
things. Therefore we should not judge of the inten-
tion of the lawgiver otherwise than by the words of
On the contrary, Hilary says (De Trin. iv.): The
meaning of what is said is according to the motive
for saying it: because things are not subject to speech,
but speech to things. Therefore we should take ac-
count of the motive of the lawgiver, rather than of
his very words.
f answer that, As stated above (A. 4), every law
is directed to the common weal of men, and derives
OF THE POWER OF HUMAN LAW 103
the force and nature of law accordingly. Hence the
jurist says:* By no reason of law, or favoiir of equity,
is it allowable for us to interpret harshly, and render
burdensome, those useful measures which have been
enacted for the welfare of man. Now it happens often
that the observance of some point of law conduces to
the common weal in the majority of instances, and
yet, in some cases, is very hurtful. Since then the law-
giver cannot have in view every single case, he shapes
the law according to what happens most frequently,
by directing his attention to the common good.
Wherefore if a case arise wherein the observance of
that law would be hurtful to the general welfare, it
should not be observed. For instance, suppose that in
a beseiged city it be an established law that the gates
of the city are to be kept closed, this is good for
public welfare as a general rule: but, if it were to
happen that the enemy are in pursuit of certain citi-
zens, who are defenders of the city, it would be a
great loss to the city, if the gates were not opened
to them: and so in that case the gates ought to be
opened, contrary to the letter of the law, in order to
maintain the common weal, which the lawgiver had
Nevertheless it must be noted, that if the observ-
ance of the law according to the letter does not in-
volve any sudden risk needing instant remedy, it is
not competent for everyone to expound what is use-
ful and what is not useful to the state: those alone
can do this who are in authority, and who, on account
* Pandect. Justin, lib. i. ff., tit. 3, De Leg. et Senat.
104 TREATISE ON LAW
of suchlike cases, have the power to dispense from the
laws. If, however, the peril be so sudden as not to al-
low of the delay involved by referring the matter to
authority, the mere necessity brings with it a dispensa-
tion, since necessity knows no law.
Reply Ob), i. He who in case of necessity acts
beside the letter of the law, does not judge of the law;
but of a particular case in which he sees that the
letter of the law is not to be observed.
Reply Obj. 2. He who follows the intention of the
lawgiver, does not interpret the law simply; but in a
case in which it is evident, by reason of the manifest
harm, that the lawgiver intended otherwise. For if it
be a matter of doubt, he must either act according to
the letter of the law, or consult those in power.
Reply Obj. 3. No man is so wise as to be able to
take account of every single case; wherefore he is not
able sufficiently to express in words all those things
that are suitable for the end he has in view. And even
if a lawgiver were able to take all the cases into con-
sideration, he ought not to mention them all, in order
to avoid confusion: but should frame the law accord-
ing to that which is of most common occurrence.
OF CHANGE IN LAWS IOJ
OF CHANGE IN LAWS
(In Four Articles)
must now consider change in laws: under which
head there are four points of inquiry: (i) Whether
human law is changeable? (2) Whether it should be
always changed, whenever anything better occurs?
(3) Whether it is abolished by custom, and whether
custom obtains the force of law? (4) Whether the
application of human law should be changed by dis-
pensation of those in authority?
WHETHER HUMAN LAW SHOULD BE CHANGED
IN ANY WAY?
We proceed thus to the First Article:
Objection i. It would seem that human law should
not be changed in any way at all. Because human law is
derived from the natural law, as stated above (Q.
XCV., A. 2) . But the natural law endures unchange-
ably. Therefore human law should also remain with-
out any change.
Obj. 2. Further, as the Philosopher says (Ethic, v.
106 TREATISE ON LAW
5 ) , a measure should be absolutely stable. But human
law is the measure of human acts, as stated above
(Q. XC, AA. i, 2). Therefore it should remain
Qbj. 3. Further, it is of the essence of law to be
just and right, as stated above (Q. XCV., A. 2).
But that which is right once is right always. There-
fore that which is law once, should be always law.
On the contrary y Augustine says (De Lib. Arb. i.
6) : A temporal law, however just, may be justly
changed in course of time.
I answer that) As stated above (Q. XCL, A. 3),
human law is a dictate of reason, whereby human acts
are directed. Thus there may be two causes for the
just change of human law: one on the part of reason;
the other on the part of man whose acts are regulated
by law. The cause on the part of reason is that it
seems natural to human reason to advance gradually
from the imperfect to the perfect. Hence, in specula-
tive sciences, we see that the teaching of the early
philosophers was imperfect, and that it was after-
wards perfected by those who succeeded them. So also
in practical matters: for those who first endeavoured
to discover something useful for the human commun-
ity, not being able by themselves to take everything
into consideration, set up certain institutions which
were deficient in many ways; and these were changed
by subsequent lawgivers who made institutions that
might prove less frequently deficient in respect of the
On the part of man, whose acts are regulated by
OF CHANGE IN LAWS IO/
law, the law can be rightly changed on account of
the changed condition of man, to whom different
things are expedient according to the difference of his
condition. An example is proposed by Augustine (De
Lib. Arb. i. 6) : If the people have a sense of modera-
tion and responsibility, and are most careful guardians
of the common weal, it is right to enact a law allow-
ing such a people to choose their own magistrates for
the government of the commonwealth. But if, as time
goes on, the same people become so corrupt as to sell
their votes, and entrust the government to scoundrels
and criminals; then the right of appointing their
public officials is rightly forfeit to such a people, and
the choice devolves to a few good men.
Reply obj. i. The natural law is a participation of
the eternal law, as stated above (Q. XCL, A. 2), and
therefore endures without change, owing to the un-
changeableness and perfection of the Divine Reason,
the Author of nature. But the reason of man is
changeable and imperfect: wherefore his law is sub-
ject to change. Moreover the natural law contains
certain universal precepts, which are everlasting:
whereas human law contains certain particular pre-
cepts, according to various emergencies.
Reply Obj. 2. A measure should be as enduring as
possible. But nothing can be absolutely unchangeable
in things that are subject to change. And therefore
human law cannot be altogether unchangeable.
Reply Obj. 3. In corporal things, right is predicated
absolutely: and therefore, as far as itself is concerned,
always remains right. But right is predicated of law
108 TREATISE ON LAW
with reference to the common weal, to which one and
the same thing is not always adapted, as stated above:
wherefore rectitude of this kind is subject to change.
WHETHER HUMAN LAW SHOULD ALWAYS BE
CHANGED, WHENEVER SOMETHING BETTER
We proceed thus to the Second Article:
Objection i. It would seem that human law should
be changed, whenever something better occurs. Be-
cause human laws are devised by human reason, like
other arts. But in the other arts, the tenets of for-
mer times give place to others, if something better
occurs. Therefore the same should apply to human
Qbj. 2. Further, by taking note of the past we can
provide for the future. Now unless human laws had
been changed when it was found possible to improve
them, considerable inconvenience would have ensued;
because the laws of old were crude in many points.
Therefore it seems that laws should be changed, when-
ever anything better occurs to be enacted.
Obj. 3. Further, human laws are enacted about sin-
gle acts of man. But we cannot acquire perfect knowl-
edge in singular matters, except by experience, which
requires time, as stated in Ethic, ii. Therefore it seems
OF CHANGE IN LAWS 10^
that as time goes on it is possible for something better
to occur for legislation.
On the contrary 9 It is stated in the Decretals (Dist.
xii. 5 ) : It is absurd, and a detestable shame, that -we
should suffer those traditions to be changed which we
have received from the fathers of old.
I answer that, As stated above (A. i), human law
is rightly changed, in so far as such change is con-
ducive to the common weal. But, to a certain extent,
the mere change of law is of itself prejudicial to the
common good: because custom avails much for the
observance of laws, seeing that what is done contrary
to general custom, even in slight matters, is looked
upon as grave. Consequently, when a law is changed,
the binding power of the law is diminished, in so far
as custom is abolished. Wherefore human law should
never be changed, unless, in some way or other, the
common weal be compensated according to the extent
of the harm done in this respect. Such compensation
may arise either from some very great and very evi-
dent benefit conferred by the new enactment; or
from the extreme urgency of the case, due to the fact
that either the existing law is clearly unjust, or its
observance extremely harmful. Wherefore the jurist
says* that in establishing new laws, there should be
evidence of the benefit to be derived, before departing
from a law which has long been considered just.
Reply Ob}, i. Rules of art derive their force from
reason alone: and therefore whenever something better
* Pandect. Justin, lib. i. tf., tit. 4, De Constit. Princip.
110 TREATISE ON LAW
occurs, the rule followed hitherto should be changed.
But laws derive very great force from custom, as the
Philosopher states (Polit. ii. 5): consequently they
should not be quickly changed.
Reply Obj. 2. This argument proves that laws
ought to be changed: not in view of any improve-
ment, but for the sake of a great benefit or in a case
of great urgency, as stated above. This answer applies
also to the Third Objection.
WHETHER CUSTOM CAN OBTAIN FORCE OF LAV?
We proceed thus to the Third Article:
Objection i . It would seem that custom cannot ob-
tain force of law, nor abolish a law. Because human
law is derived from the natural law and from the
Divine law, as stated above (Q. XCIIL, A. 3; Q.
XCV.j A. 2). But human custom cannot change
either the law of nature or the Divine law. Therefore
neither can it change human law.
Obj. 2. Further, many evils cannot make one good.
But he who first acted against the law, did evil.
Therefore by multiplying such acts, nothing good is
the result. Now a law is something good; since it is a
rule of human acts. Therefore law is not abolished by
custom, so that the mere custom should obtain force
OF CHANGE IN LAWS III
Obj. 3. Further, the framing of laws belongs to
those public men whose business it is to govern the
community; wherefore private individuals cannot
make laws. But custom grows by the acts of private in-
dividuals. Therefore custom cannot obtain force of
law, so as to abolish the law.
On the contrary, Augustine says (Ep. ad Casulan,
xxxvi.) : The customs of God's people and the institu-
tions of our ancestors are to be considered as laws.
And those who throw contempt on the customs of
the Church ought to be punished as those who disobey
the law of God.
I answer that 9 All law proceeds from the reason and
will of the lawgiver; the Divine and natural laws
from the reasonable will of God; the human law
from the will of man, regulated by reason. Now just
as human reason and will, in practical matters, may
be made manifest by speech, so may they be made
known by deeds: since seemingly a man chooses as
good that which he carries into execution. But it is
evident that by human speech, law can be both
changed and expounded, in so far as it manifests the
interior movement and thought of human reason.
Wherefore by actions also, especially if they be re-
peated, so as to make a custom, law can be changed
and expounded; and also something can be established
which obtains force of law, in so far as by repeated
external actions, the inward movement of the will,
and concepts of reason are most effectually declared;
for when a thing is done again and again, it seems to
112 TREATISE ON LAW
proceed from a deliberate judgment of reason. Ac-
cordingly, custom has the force of a law, abolishes
law, and is the interpreter of law.
Reply Obj. i. The natural and Divine laws proceed
from the Divine will, as stated above. Wherefore they
cannot be changed by a custom proceeding from the
will of man, but only by Divine authority. Hence it
is that no custom can prevail over the Divine or
natural laws: for Isidore says (Synon. ii. 16). Let
custom yield to authority: evil customs should be
eradicated by law and reason.
Reply Ob}. 2. As stated above (Q. XCVL, A. 6),
human laws fail in some cases: wherefore it is possible
sometimes to act beside the law; namely, in a case where
the law fails; yet the act will not be evil. And when
such cases are multiplied, by reason of some change in
man, then custom shows that the law is no longer use-
ful: just as it might be declared by the verbal promul-
gation of a law to the contrary. If, however, the same
reason remains, for which the law was useful hitherto,
then it is not the custom that prevails against the law,
but the law that overcomes the custom: unless perhaps
the sole reason for the law seeming useless, be that it
is not possible according to the custom of the coun-
try* which has been stated to be one of the condi-
tions of law. For it is not easy to set aside the cus-
tom of a whole people.
Reply Obj. 3. The people among whom a custom
is introduced may be of two conditions. For if they
are free, and able to make their own laws, the consent
* C/. Q. XCV., A. 3.
OF CHANGE IN LAWS 113
of the whole people expressed by a custom counts far
more in favour of a particular observance, than does
the authority of the sovereign, who has not the power
to frame laws, except as representing the people.
"Wherefore although each individual cannot make
laws, yet the whole people can. If however the peo-
ple have not the free power to make their own laws,
or to abolish a law made by a higher authority; never-
theless with such a people a prevailing custom ob-
tains force of law, in so far as it is tolerated by those
to whom it belongs to make laws for that people: be-
cause by the very fact that they tolerate it they seem
to approve of that which is introduced by custom.
WHETHER THE RULERS OF THE PEOPLE CAN
DISPENSE FROM HUMAN LAWS?
We proceed thus to the "Fourth Article:
Objection i. It would seem that the rulers of the
people cannot dispense from human laws. For the
law is established for the common weal, as Isidore
says (Etym. v. 21). But the common good should
not be set aside for the private convenience of an
individual: because, as the Philosopher says (Ethic.
i. 2), the good of the nation is more godlike than the
good of one man. Therefore it seems that a man.
should not be dispensed from acting in compliance
with the general law.
114 TREATISE ON LAW
Obj. 2. Further, those who are placed over others
are commanded as follows (Deut. i. 17): You shall
hear the little as well as the great; neither shall you
respect any man's person, because it is the judgment
of God. But to allow one man to do that which is
equally forbidden to all, seems to be respect of per-
sons. Therefore the rulers of a community cannot
grant such dispensations, since this is against a precept
of the Divine law.
Obj. 3. Further, human law, in order to be just,
should accord with the natural and Divine laws: else
it would not foster religion, nor be helpful to disci-
pline, which is requisite to the nature of law, as laid
down by Isidore (Etym. v. 3). But no man can dis-
pense from the Divine and natural laws. Neither,
therefore, can he dispense from the human law.
On the contrary, The Apostle says (i Cor. ix. 17) :
A dispensation is committed to me.
1 answer that, Dispensation, properly speaking, de-
notes a measuring out to individuals of some common
goods: thus the head of a household is called a dispen-
ser, because to each member of the household he dis-
tributes work and necessaries of life in due weight
and measure. Accordingly in every community a
man is said to dispense, from the very fact that he
directs how some general precept is to be fulfilled by
each individual. Now it happens at times that a pre-
cept, which is conducive to the common weal as a
general rule, is not good for a particular individual, or
in some particular case, either because it would hinder
some greater good, or because it would be the occasion
OF CHANGE IN LAWS 115
of some evil, as explained above (Q. XCVL, A. 6).
But it would be dangerous to leave this to the discre-
tion of each individual, except perhaps by reason of
an evident and sudden emergency, as stated above
(ibid.). Consequently he who is placed over a com-
munity is empowered to dispense in a human law that
rests upon his authority, so that, when the law fails
in its application to persons or circumstances, he may
allow the precept of the law not to be observed. If
however he grant this permission without any such
reason, and of his mere will, he will be an unfaithful
or an imprudent dispenser: unfaithful, if he has not
the common good in view; imprudent, if he ignores
the reasons for granting dispensations. Hence Our
Lord says (Luke xii. 42): Who, thinkest thou, is the
faithful and whe dispenser (Douay, steivard) , whom
his lord setteth over his family?
Reply Obj. i . "When a person is dispensed from ob-
serving the general law, this should not be done to
the prejudice of, but with the intention of benefiting,
the common good.
Reply Obj. 2. It is not respect of persons if unequal
measures are served out to those who are themselves
unequal. Wherefore when the condition of any per-
son requires that he should reasonably receive special
treatment, it is not respect of persons if he be the
object of special favour.
Reply Obj. 3. Natural law, so far as it contains
general precepts, which never fail, does not allow of
dispensation. In the other precepts, however, which
are as conclusions of the general precepts, man some-
II 6 TREATISE ON LAW
times grants a dispensation: for instance, that a loan
should not be paid back to the betrayer of his coun-
try, or something similar. But to the Divine law each
man stands as a private person to the public law to
which he is subject. Wherefore just as none can
dispense from public human law, except the man
from whom the law derives its authority, or his dele-
gate; so, in the precepts of the Divine law, which are
from God, none can dispense but God, or the man
to whom He may give special power for that purpose.